diff --git a/quic/core/quic_flags_list.h b/quic/core/quic_flags_list.h
index e76c6e3..e563119 100644
--- a/quic/core/quic_flags_list.h
+++ b/quic/core/quic_flags_list.h
@@ -68,7 +68,7 @@
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_unified_iw_options, false)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_use_circular_deque_for_unacked_packets_v2, true)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_use_encryption_level_context, false)
-QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_use_write_or_buffer_data_at_level, false)
+QUIC_FLAG(FLAGS_quic_reloadable_flag_quic_use_write_or_buffer_data_at_level, true)
 QUIC_FLAG(FLAGS_quic_reloadable_flag_send_quic_fallback_server_config_on_leto_error, false)
 QUIC_FLAG(FLAGS_quic_restart_flag_dont_fetch_quic_private_keys_from_leto, false)
 QUIC_FLAG(FLAGS_quic_restart_flag_http2_parse_priority_update_frame, false)