Engineering work is taking place between Oxford and Didcot Parkway, closing some lines early on Sunday morning.
As a result, the 07:53 Oxford to London Paddington service will start from Didcot Parkway at 08:05.
You can use other Great Western Railway services between Oxford and Didcot Parkway at no extra cost.
Check before you travel:
You can plan your journey using the National Rail Journey Planner.