diff --git a/quic/core/quic_connection.cc b/quic/core/quic_connection.cc
index b52d4d1..f152e6e 100644
--- a/quic/core/quic_connection.cc
+++ b/quic/core/quic_connection.cc
@@ -324,7 +324,6 @@
 
   support_multiple_connection_ids_ =
       version().HasIetfQuicFrames() &&
-      GetQuicRestartFlag(quic_time_wait_list_support_multiple_cid_v2) &&
       GetQuicRestartFlag(
           quic_dispatcher_support_multiple_cid_per_connection_v2);
 
diff --git a/quic/core/quic_dispatcher.cc b/quic/core/quic_dispatcher.cc
index 3e33c29..7bf4576 100644
--- a/quic/core/quic_dispatcher.cc
+++ b/quic/core/quic_dispatcher.cc
@@ -177,7 +177,6 @@
     SerializeConnectionClosePacket(error_code, error_details);
 
     time_wait_list_manager_->AddConnectionIdToTimeWait(
-        server_connection_id_,
         QuicTimeWaitListManager::SEND_TERMINATION_PACKETS,
         TimeWaitConnectionInfo(ietf_quic, collector_.packets(),
                                std::move(active_connection_ids),
@@ -896,7 +895,7 @@
     QUIC_CODE_COUNT(quic_v44_add_to_time_wait_list_with_stateless_reset);
   }
   time_wait_list_manager_->AddConnectionIdToTimeWait(
-      server_connection_id, action,
+      action,
       TimeWaitConnectionInfo(
           connection->version().HasIetfInvariantHeader(),
           connection->termination_packets(),
@@ -1119,9 +1118,8 @@
                   << ", error_code:" << error_code
                   << ", error_details:" << error_details;
     time_wait_list_manager_->AddConnectionIdToTimeWait(
-        server_connection_id, action,
-        TimeWaitConnectionInfo(format != GOOGLE_QUIC_PACKET, nullptr,
-                               {server_connection_id}));
+        action, TimeWaitConnectionInfo(format != GOOGLE_QUIC_PACKET, nullptr,
+                                       {server_connection_id}));
     return;
   }
 
@@ -1159,7 +1157,7 @@
       /*ietf_quic=*/format != GOOGLE_QUIC_PACKET, use_length_prefix,
       /*versions=*/{}));
   time_wait_list_manager()->AddConnectionIdToTimeWait(
-      server_connection_id, QuicTimeWaitListManager::SEND_TERMINATION_PACKETS,
+      QuicTimeWaitListManager::SEND_TERMINATION_PACKETS,
       TimeWaitConnectionInfo(/*ietf_quic=*/format != GOOGLE_QUIC_PACKET,
                              &termination_packets, {server_connection_id}));
 }
diff --git a/quic/core/quic_dispatcher.h b/quic/core/quic_dispatcher.h
index 3d36812..0073666 100644
--- a/quic/core/quic_dispatcher.h
+++ b/quic/core/quic_dispatcher.h
@@ -491,7 +491,6 @@
       GetQuicRestartFlag(quic_use_recent_reset_addresses);
 
   const bool support_multiple_cid_per_connection_ =
-      GetQuicRestartFlag(quic_time_wait_list_support_multiple_cid_v2) &&
       GetQuicRestartFlag(
           quic_dispatcher_support_multiple_cid_per_connection_v2);
 };
diff --git a/quic/core/quic_dispatcher_test.cc b/quic/core/quic_dispatcher_test.cc
index a5bf226..2851ff5 100644
--- a/quic/core/quic_dispatcher_test.cc
+++ b/quic/core/quic_dispatcher_test.cc
@@ -897,7 +897,7 @@
   EXPECT_CALL(*time_wait_list_manager_,
               ProcessPacket(_, _, connection_id, _, _, _))
       .Times(1);
-  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _, _))
+  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _))
       .Times(0);
   ProcessPacket(client_address, connection_id, true, "data");
 }
@@ -913,7 +913,7 @@
   EXPECT_CALL(*time_wait_list_manager_,
               ProcessPacket(_, _, connection_id, _, _, _))
       .Times(0);
-  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _, _))
+  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _))
       .Times(0);
   EXPECT_CALL(*time_wait_list_manager_, SendPublicReset(_, _, _, _, _, _))
       .Times(1);
@@ -935,7 +935,7 @@
   EXPECT_CALL(*dispatcher_, CreateQuicSession(_, _, _, _, _, _)).Times(0);
   EXPECT_CALL(*time_wait_list_manager_, ProcessPacket(_, _, _, _, _, _))
       .Times(0);
-  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _, _))
+  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _))
       .Times(0);
   // Verify small packet is silently dropped.
   EXPECT_CALL(*time_wait_list_manager_, SendPublicReset(_, _, _, _, _, _))
@@ -955,7 +955,7 @@
   EXPECT_CALL(*dispatcher_, CreateQuicSession(_, _, _, _, _, _)).Times(0);
   EXPECT_CALL(*time_wait_list_manager_, ProcessPacket(_, _, _, _, _, _))
       .Times(0);
-  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _, _))
+  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _))
       .Times(0);
   if (GetQuicRestartFlag(quic_drop_invalid_flags)) {
     EXPECT_CALL(*time_wait_list_manager_, SendPublicReset(_, _, _, _, _, _))
@@ -1201,7 +1201,7 @@
       .Times(0);
   EXPECT_CALL(*time_wait_list_manager_, ProcessPacket(_, _, _, _, _, _))
       .Times(0);
-  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _, _))
+  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _))
       .Times(0);
   ProcessPacket(client_address, TestConnectionId(1), /*has_version_flag=*/true,
                 "data");
@@ -1220,7 +1220,7 @@
   EXPECT_CALL(*dispatcher_, CreateQuicSession(_, _, _, _, _, _)).Times(0);
   EXPECT_CALL(*time_wait_list_manager_, ProcessPacket(_, _, _, _, _, _))
       .Times(0);
-  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _, _))
+  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _))
       .Times(0);
   ProcessFirstFlight(client_address, EmptyQuicConnectionId());
 }
@@ -1236,7 +1236,7 @@
   EXPECT_CALL(*dispatcher_, CreateQuicSession(_, _, _, _, _, _)).Times(0);
   EXPECT_CALL(*time_wait_list_manager_, ProcessPacket(_, _, _, _, _, _))
       .Times(0);
-  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _, _))
+  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _))
       .Times(0);
   absl::string_view cid_str = "123456789abcdefg123456789abcdefg";
   QuicConnectionId invalid_connection_id(cid_str.data(), cid_str.length());
@@ -1658,7 +1658,7 @@
 
   EXPECT_CALL(*dispatcher_, CreateQuicSession(_, _, _, _, _, _)).Times(0);
   EXPECT_CALL(*time_wait_list_manager_, SendPacket(_, _, _)).Times(0);
-  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _, _))
+  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _))
       .Times(0);
   ProcessPacket(client_address, TestConnectionId(1), /*has_version_flag=*/true,
                 version_, SerializeCHLO(), /*full_padding=*/false,
@@ -1811,7 +1811,7 @@
   EXPECT_CALL(*dispatcher_, CreateQuicSession(_, _, _, _, _, _)).Times(0);
   EXPECT_CALL(*time_wait_list_manager_, ProcessPacket(_, _, _, _, _, _))
       .Times(0);
-  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _, _))
+  EXPECT_CALL(*time_wait_list_manager_, AddConnectionIdToTimeWait(_, _))
       .Times(0);
 
   ProcessPacket(client_address, connection_id, true, "data",
@@ -2126,7 +2126,6 @@
  public:
   QuicDispatcherSupportMultipleConnectionIdPerConnectionTest()
       : QuicDispatcherTestBase(crypto_test_utils::ProofSourceForTesting()) {
-    SetQuicRestartFlag(quic_time_wait_list_support_multiple_cid_v2, true);
     SetQuicRestartFlag(quic_dispatcher_support_multiple_cid_per_connection_v2,
                        true);
     dispatcher_ = std::make_unique<NiceMock<TestDispatcher>>(
diff --git a/quic/core/quic_flags_list.h b/quic/core/quic_flags_list.h
index d0a1bec..ac7efde 100644
--- a/quic/core/quic_flags_list.h
+++ b/quic/core/quic_flags_list.h
@@ -105,8 +105,6 @@
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_donot_reset_ideal_next_packet_send_time, false)
 // If true, suppress crypto data write in mid of packet processing.
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_suppress_write_mid_packet_processing, true)
-// If true, time_wait_list can support multiple connection IDs.
-QUIC_FLAG(FLAGS_quic_restart_flag_quic_time_wait_list_support_multiple_cid_v2, true)
 // If true, use BBRv2 as the default congestion controller. Takes precedence over --quic_default_to_bbr.
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_default_to_bbr_v2, false)
 // If true, use new connection ID in connection migration.
diff --git a/quic/core/quic_time_wait_list_manager.cc b/quic/core/quic_time_wait_list_manager.cc
index ef64125..c92b636 100644
--- a/quic/core/quic_time_wait_list_manager.cc
+++ b/quic/core/quic_time_wait_list_manager.cc
@@ -91,9 +91,6 @@
 QuicTimeWaitListManager::ConnectionIdMap::iterator
 QuicTimeWaitListManager::FindConnectionIdDataInMap(
     const QuicConnectionId& connection_id) {
-  if (!use_indirect_connection_id_map_) {
-    return connection_id_map_.find(connection_id);
-  }
   auto it = indirect_connection_id_map_.find(connection_id);
   if (it == indirect_connection_id_map_.end()) {
     return connection_id_map_.end();
@@ -106,12 +103,8 @@
     int num_packets,
     TimeWaitAction action,
     TimeWaitConnectionInfo info) {
-  if (use_indirect_connection_id_map_) {
-    QUIC_RESTART_FLAG_COUNT_N(quic_time_wait_list_support_multiple_cid_v2, 1,
-                              3);
-    for (const auto& cid : info.active_connection_ids) {
-      indirect_connection_id_map_[cid] = canonical_connection_id;
-    }
+  for (const auto& cid : info.active_connection_ids) {
+    indirect_connection_id_map_[cid] = canonical_connection_id;
   }
   ConnectionIdData data(num_packets, clock_->ApproximateNow(), action,
                         std::move(info));
@@ -121,24 +114,18 @@
 
 void QuicTimeWaitListManager::RemoveConnectionDataFromMap(
     ConnectionIdMap::iterator it) {
-  if (use_indirect_connection_id_map_) {
-    QUIC_RESTART_FLAG_COUNT_N(quic_time_wait_list_support_multiple_cid_v2, 2,
-                              3);
-    for (const auto& cid : it->second.info.active_connection_ids) {
-      indirect_connection_id_map_.erase(cid);
-    }
+  for (const auto& cid : it->second.info.active_connection_ids) {
+    indirect_connection_id_map_.erase(cid);
   }
   connection_id_map_.erase(it);
 }
 
 void QuicTimeWaitListManager::AddConnectionIdToTimeWait(
-    QuicConnectionId connection_id,
     TimeWaitAction action,
     TimeWaitConnectionInfo info) {
   QUICHE_DCHECK(!info.active_connection_ids.empty());
   const QuicConnectionId& canonical_connection_id =
-      use_indirect_connection_id_map_ ? info.active_connection_ids.front()
-                                      : connection_id;
+      info.active_connection_ids.front();
   QUICHE_DCHECK(action != SEND_TERMINATION_PACKETS ||
                 !info.termination_packets.empty());
   QUICHE_DCHECK(action != DO_NOTHING || info.ietf_quic);
@@ -154,26 +141,18 @@
       GetQuicFlag(FLAGS_quic_time_wait_list_max_connections);
   QUICHE_DCHECK(connection_id_map_.empty() ||
                 num_connections() < static_cast<size_t>(max_connections));
-  if (use_indirect_connection_id_map_ && new_connection_id) {
-    QUIC_RESTART_FLAG_COUNT_N(quic_time_wait_list_support_multiple_cid_v2, 3,
-                              3);
+  if (new_connection_id) {
     for (const auto& cid : info.active_connection_ids) {
       visitor_->OnConnectionAddedToTimeWaitList(cid);
     }
   }
   AddConnectionIdDataToMap(canonical_connection_id, num_packets, action,
                            std::move(info));
-  if (!use_indirect_connection_id_map_ && new_connection_id) {
-    visitor_->OnConnectionAddedToTimeWaitList(canonical_connection_id);
-  }
 }
 
 bool QuicTimeWaitListManager::IsConnectionIdInTimeWait(
     QuicConnectionId connection_id) const {
-  if (use_indirect_connection_id_map_) {
-    return indirect_connection_id_map_.contains(connection_id);
-  }
-  return connection_id_map_.contains(connection_id);
+  return indirect_connection_id_map_.contains(connection_id);
 }
 
 void QuicTimeWaitListManager::OnBlockedWriterCanWrite() {
diff --git a/quic/core/quic_time_wait_list_manager.h b/quic/core/quic_time_wait_list_manager.h
index fe15159..a084484 100644
--- a/quic/core/quic_time_wait_list_manager.h
+++ b/quic/core/quic_time_wait_list_manager.h
@@ -99,14 +99,13 @@
   QuicTimeWaitListManager& operator=(const QuicTimeWaitListManager&) = delete;
   ~QuicTimeWaitListManager() override;
 
-  // Adds the given connection_id to time wait state for time_wait_period_.
-  // If |termination_packets| are provided, copies of these packets will be sent
-  // when a packet with this connection ID is processed. Any termination packets
-  // will be move from |termination_packets| and will become owned by the
-  // manager. |action| specifies what the time wait list manager should do when
-  // processing packets of the connection.
-  virtual void AddConnectionIdToTimeWait(QuicConnectionId connection_id,
-                                         TimeWaitAction action,
+  // Adds the connection IDs in info to time wait state for time_wait_period_.
+  // If |info|.termination_packets are provided, copies of these packets will be
+  // sent when a packet with one of these connection IDs is processed. Any
+  // termination packets will be move from |info|.termination_packets and will
+  // become owned by the manager. |action| specifies what the time wait list
+  // manager should do when processing packets of the connection.
+  virtual void AddConnectionIdToTimeWait(TimeWaitAction action,
                                          TimeWaitConnectionInfo info);
 
   // Returns true if the connection_id is in time wait state, false otherwise.
@@ -337,11 +336,6 @@
 
   // Interface that manages blocked writers.
   Visitor* visitor_;
-
-  // When this is default true, remove the connection_id argument of
-  // AddConnectionIdToTimeWait.
-  bool use_indirect_connection_id_map_ =
-      GetQuicRestartFlag(quic_time_wait_list_support_multiple_cid_v2);
 };
 
 }  // namespace quic
diff --git a/quic/core/quic_time_wait_list_manager_test.cc b/quic/core/quic_time_wait_list_manager_test.cc
index 49e8b27..3610535 100644
--- a/quic/core/quic_time_wait_list_manager_test.cc
+++ b/quic/core/quic_time_wait_list_manager_test.cc
@@ -157,7 +157,7 @@
     termination_packets.push_back(std::unique_ptr<QuicEncryptedPacket>(
         new QuicEncryptedPacket(nullptr, 0, false)));
     time_wait_list_manager_.AddConnectionIdToTimeWait(
-        connection_id, QuicTimeWaitListManager::SEND_TERMINATION_PACKETS,
+        QuicTimeWaitListManager::SEND_TERMINATION_PACKETS,
         TimeWaitConnectionInfo(false, &termination_packets, {connection_id}));
   }
 
@@ -167,9 +167,8 @@
       QuicTimeWaitListManager::TimeWaitAction action,
       std::vector<std::unique_ptr<QuicEncryptedPacket>>* packets) {
     time_wait_list_manager_.AddConnectionIdToTimeWait(
-        connection_id, action,
-        TimeWaitConnectionInfo(version.HasIetfInvariantHeader(), packets,
-                               {connection_id}));
+        action, TimeWaitConnectionInfo(version.HasIetfInvariantHeader(),
+                                       packets, {connection_id}));
   }
 
   bool IsConnectionIdInTimeWait(QuicConnectionId connection_id) {
@@ -450,10 +449,6 @@
 
 TEST_F(QuicTimeWaitListManagerTest,
        CleanUpOldConnectionIdsForMultipleConnectionIdsPerConnection) {
-  if (!GetQuicRestartFlag(quic_time_wait_list_support_multiple_cid_v2)) {
-    return;
-  }
-
   connection_id_ = TestConnectionId(7);
   const size_t kConnectionCloseLength = 100;
   EXPECT_CALL(visitor_, OnConnectionAddedToTimeWaitList(connection_id_));
@@ -467,7 +462,7 @@
   std::vector<QuicConnectionId> active_connection_ids{connection_id_,
                                                       TestConnectionId(8)};
   time_wait_list_manager_.AddConnectionIdToTimeWait(
-      connection_id_, QuicTimeWaitListManager::SEND_CONNECTION_CLOSE_PACKETS,
+      QuicTimeWaitListManager::SEND_CONNECTION_CLOSE_PACKETS,
       TimeWaitConnectionInfo(/*ietf_quic=*/true, &termination_packets,
                              active_connection_ids, QuicTime::Delta::Zero()));
 
@@ -675,7 +670,7 @@
       std::unique_ptr<QuicEncryptedPacket>(new QuicEncryptedPacket(
           new char[kConnectionCloseLength], kConnectionCloseLength, true)));
   time_wait_list_manager_.AddConnectionIdToTimeWait(
-      connection_id_, QuicTimeWaitListManager::SEND_TERMINATION_PACKETS,
+      QuicTimeWaitListManager::SEND_TERMINATION_PACKETS,
       TimeWaitConnectionInfo(/*ietf_quic=*/true, &termination_packets,
                              {connection_id_}));
 
@@ -701,7 +696,7 @@
           new char[kConnectionCloseLength], kConnectionCloseLength, true)));
   // Add a CONNECTION_CLOSE termination packet.
   time_wait_list_manager_.AddConnectionIdToTimeWait(
-      connection_id_, QuicTimeWaitListManager::SEND_CONNECTION_CLOSE_PACKETS,
+      QuicTimeWaitListManager::SEND_CONNECTION_CLOSE_PACKETS,
       TimeWaitConnectionInfo(/*ietf_quic=*/true, &termination_packets,
                              {connection_id_}));
   EXPECT_CALL(writer_, WritePacket(_, kConnectionCloseLength,
@@ -717,10 +712,6 @@
 
 TEST_F(QuicTimeWaitListManagerTest,
        SendConnectionClosePacketsForMultipleConnectionIds) {
-  if (!GetQuicRestartFlag(quic_time_wait_list_support_multiple_cid_v2)) {
-    return;
-  }
-
   connection_id_ = TestConnectionId(7);
   const size_t kConnectionCloseLength = 100;
   EXPECT_CALL(visitor_, OnConnectionAddedToTimeWaitList(connection_id_));
@@ -734,7 +725,7 @@
   std::vector<QuicConnectionId> active_connection_ids{connection_id_,
                                                       TestConnectionId(8)};
   time_wait_list_manager_.AddConnectionIdToTimeWait(
-      connection_id_, QuicTimeWaitListManager::SEND_CONNECTION_CLOSE_PACKETS,
+      QuicTimeWaitListManager::SEND_CONNECTION_CLOSE_PACKETS,
       TimeWaitConnectionInfo(/*ietf_quic=*/true, &termination_packets,
                              active_connection_ids, QuicTime::Delta::Zero()));
 
diff --git a/quic/test_tools/mock_quic_time_wait_list_manager.cc b/quic/test_tools/mock_quic_time_wait_list_manager.cc
index 6274f20..63858c9 100644
--- a/quic/test_tools/mock_quic_time_wait_list_manager.cc
+++ b/quic/test_tools/mock_quic_time_wait_list_manager.cc
@@ -18,9 +18,9 @@
     : QuicTimeWaitListManager(writer, visitor, clock, alarm_factory) {
   // Though AddConnectionIdToTimeWait is mocked, we want to retain its
   // functionality.
-  EXPECT_CALL(*this, AddConnectionIdToTimeWait(_, _, _))
+  EXPECT_CALL(*this, AddConnectionIdToTimeWait(_, _))
       .Times(testing::AnyNumber());
-  ON_CALL(*this, AddConnectionIdToTimeWait(_, _, _))
+  ON_CALL(*this, AddConnectionIdToTimeWait(_, _))
       .WillByDefault(
           Invoke(this, &MockTimeWaitListManager::
                            QuicTimeWaitListManager_AddConnectionIdToTimeWait));
diff --git a/quic/test_tools/mock_quic_time_wait_list_manager.h b/quic/test_tools/mock_quic_time_wait_list_manager.h
index 12bf080..1d3cfd5 100644
--- a/quic/test_tools/mock_quic_time_wait_list_manager.h
+++ b/quic/test_tools/mock_quic_time_wait_list_manager.h
@@ -19,19 +19,15 @@
                           QuicAlarmFactory* alarm_factory);
   ~MockTimeWaitListManager() override;
 
-  MOCK_METHOD(void,
-              AddConnectionIdToTimeWait,
-              (QuicConnectionId connection_id,
-               QuicTimeWaitListManager::TimeWaitAction action,
+  MOCK_METHOD(void, AddConnectionIdToTimeWait,
+              (QuicTimeWaitListManager::TimeWaitAction action,
                quic::TimeWaitConnectionInfo info),
               (override));
 
   void QuicTimeWaitListManager_AddConnectionIdToTimeWait(
-      QuicConnectionId connection_id,
       QuicTimeWaitListManager::TimeWaitAction action,
       quic::TimeWaitConnectionInfo info) {
-    QuicTimeWaitListManager::AddConnectionIdToTimeWait(connection_id, action,
-                                                       std::move(info));
+    QuicTimeWaitListManager::AddConnectionIdToTimeWait(action, std::move(info));
   }
 
   MOCK_METHOD(void,