diff --git a/warehouse/models/intermediate/gtfs/int_gtfs_rt__trip_updates_trip_day_map_grouping.sql b/warehouse/models/intermediate/gtfs/int_gtfs_rt__trip_updates_trip_day_map_grouping.sql
new file mode 100644
index 0000000000..a99496f506
--- /dev/null
+++ b/warehouse/models/intermediate/gtfs/int_gtfs_rt__trip_updates_trip_day_map_grouping.sql
@@ -0,0 +1,76 @@
+{{
+    config(
+        materialized='incremental',
+        incremental_strategy='insert_overwrite',
+        partition_by={
+            'field': 'calculated_service_date_pacific',
+            'data_type': 'date',
+            'granularity': 'day',
+        },
+        cluster_by='base64_url',
+    )
+}}
+
+WITH stop_time_updates AS (
+    SELECT *
+    FROM {{ ref('fct_stop_time_updates') }}
+    WHERE {{ gtfs_rt_dt_where() }}
+),
+
+rt_feeds AS (
+    SELECT *
+    FROM {{ ref('fct_daily_rt_feed_files') }}
+),
+
+schedule_feeds AS (
+    SELECT *
+    FROM {{ ref('dim_schedule_feeds') }}
+),
+
+-- group by *both* the UTC date that data was scraped (dt) *and* calculated service date
+-- so that in the mart we can get just service date-level data
+-- this allows us to handle the dt/service_date mismatch by grouping in two stages
+int_gtfs_rt__trip_updates_trip_day_map_grouping AS (
+    SELECT
+        -- try to figure out what the service date would be to join back with schedule: fall back from explicit to imputed
+        -- TODO: it's possible that this could lead to some weirdness around midnight Pacific / in feed timezone
+        -- if `trip_start_date` is not set we theoretically should be trying to grab the date of the first arrival time per trip
+        -- because trip updates may be generated hours before the beginning of the actual trip activity
+        -- however the fact that this would occur near date boundaries is precisely why it's a bit tricky to pick the right first arrival time if trip start date is not populated
+        dt,
+        COALESCE(
+            PARSE_DATE("%Y%m%d", trip_start_date),
+            DATE(header_timestamp, schedule_feeds.feed_timezone),
+            DATE(_extract_ts, schedule_feeds.feed_timezone)) AS calculated_service_date,
+        base64_url,
+        trip_id,
+        trip_route_id,
+        trip_direction_id,
+        trip_start_time,
+        trip_start_date,
+        trip_schedule_relationship,
+        schedule_feeds.feed_timezone,
+        ARRAY_AGG(DISTINCT id) AS message_ids_array,
+        ARRAY_AGG(DISTINCT header_timestamp) AS header_timestamps_array,
+        ARRAY_AGG(DISTINCT trip_update_timestamp) AS trip_update_timestamps_array,
+        MIN(_extract_ts) AS min_extract_ts,
+        MAX(_extract_ts) AS max_extract_ts,
+        MIN(header_timestamp) AS min_header_timestamp,
+        MAX(header_timestamp) AS max_header_timestamp,
+        MIN(trip_update_timestamp) AS min_trip_update_timestamp,
+        MAX(trip_update_timestamp) AS max_trip_update_timestamp,
+        MAX(trip_update_delay) AS max_delay,
+        ARRAY_AGG(DISTINCT CASE WHEN schedule_relationship = 'SKIPPED' THEN stop_id END) AS skipped_stops_array,
+        ARRAY_AGG(DISTINCT CASE WHEN schedule_relationship = 'SCHEDULED' THEN stop_id END) AS scheduled_stops_array,
+        ARRAY_AGG(DISTINCT CASE WHEN schedule_relationship = 'CANCELED' THEN stop_id END) AS canceled_stops_array,
+        ARRAY_AGG(DISTINCT CASE WHEN schedule_relationship = 'ADDED' THEN stop_id END) AS added_stops_array,
+    FROM stop_time_updates
+    LEFT JOIN rt_feeds
+        ON stop_time_updates.base64_url = rt_feeds.base64_url
+        AND stop_time_updates.dt = rt_feeds.date
+    LEFT JOIN schedule_feeds
+        ON rt_feeds.schedule_feed_key = schedule_feeds.key
+    GROUP BY 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
+)
+
+SELECT * FROM int_gtfs_rt__trip_updates_trip_day_map_grouping
diff --git a/warehouse/models/mart/gtfs/fct_trip_updates_messages.sql b/warehouse/models/mart/gtfs/fct_trip_updates_messages.sql
index bac2301554..9a6e42da08 100644
--- a/warehouse/models/mart/gtfs/fct_trip_updates_messages.sql
+++ b/warehouse/models/mart/gtfs/fct_trip_updates_messages.sql
@@ -40,13 +40,6 @@ fct_trip_updates_messages AS (
         TIMESTAMP_DIFF(_extract_ts, header_timestamp, SECOND) AS _header_message_age,
         TIMESTAMP_DIFF(_extract_ts, trip_update_timestamp, SECOND) AS _trip_update_message_age,
         TIMESTAMP_DIFF(header_timestamp, trip_update_timestamp, SECOND) AS _trip_update_message_age_vs_header,
-        -- TODO: once #2457 merges, we should use the schedule feed timezone rather than just Pacific
-        -- we need to get individual trip instances that can be merged with schedule feed trip instances
-        COALESCE(
-            PARSE_DATE("%Y%m%d",trip_start_date),
-            DATE(trip_update_timestamp, "America/Los_Angeles"),
-            DATE(header_timestamp, "America/Los_Angeles"),
-            DATE(_extract_ts, "America/Los_Angeles")) AS calculated_service_date_pacific,
 
         header_timestamp,
         header_version,