New SEPTA regional rail schedules will go into effect Monday, marking another change after the transportation authority enacted an interim itinerary last month.

RELATED: SEPTA releases updated Regional Rail schedule

Two new trains will be added to service, while the arrival and departure times of 15 other trains on four lines will be adjusted.

The Lansdale/Doylestown line will see the biggest changes with the two new pieces of equipment and 10 adjusted schedules primarily affecting the morning commute between 5 and 9 a.m. and evening service between 4 and 8 p.m.

The West Trenton, Media/Elwyn, and Warminster lines will also see changes. All other lines will continue to follow the current interim weekday schedules previously set.

SEPTA has been enacting these changes to address crowding and station pass-ups after it removed one-third of its fleet for repairs.

See more details about the schedule changes here.