Network Rail is completing planned engineering works along the mainline between Didcot and Swindon which means GWR trains will need to use alternative routes to serve Bristol and South Wales.

There is also planned engineering works in the Paddington area until 0920, and then only half the tracks will be available for GWR, Elizabeth line and Heathrow Express trains.

This means there is a significant reduction to the train service along major routes and this has led GWR to advise customers to consider travelling on alternative days for the next two Sundays.

This coming Sunday, due to engineering work no trains will operate between London Paddington and Reading before 0920.

After 0920 a significantly reduced, amended timetable will be in place for services between London and Bristol Temple Meads, and South Wales.

Before 0920 services will start from or terminate at Reading, where customers will be able to change for Elizabeth line services to Ealing Broadway where they can change for the London Underground network.

After 0920 only one train an hour will serve Bristol and South Wales, operating on a diversionary route from Reading to Bath, before continuing to Bristol Temple Meads; Bristol Parkway; Newport and Cardiff.

Trains will resume between London Paddington and Reading, but services will be reduced as only two out of four tracks will be available. Services to destinations elsewhere across the GWR network will continue to operate as planned.

GWR Operations Director Richard Rowland said:

“We're sorry for the impact this work will have on journeys between London and Bristol and South Wales. We advise customers to change plans if possible and only travel on Sunday if absolutely necessary.

“This works means that we are only able to run very few trains on this route and those that will run will be really busy.”

As well as significantly busier trains, journeys will also take much longer. Services may also be cancelled or delayed at short notice.

To help customers, those who have already bought tickets on the route affected for Sunday, March 23 will be able to use them on Saturday, March 22 or Monday, March 24, or you can claim a full refund at GWR.com/Refunds, according to the usual terms and conditions of the ticket type.

The closure of M4 between Bath and Bristol will also affect the train operator’s ability to provide replacement bus transport, and there will be no buses between Swindon and Bristol Parkway.

Replacement buses will operate between Didcot Parkway and Swindon; Reading and Swindon; plus Bath Spa and Swindon. After 0920 train shuttle services will operate between London Paddington and Reading/Didcot Parkway.

The track renewal works continue the weekend of March 29/30, and once again a very limited service can operate between London Paddington and Bristol/South Wales. Replacement buses will however be able to run between Swindon and Bristol Parkway.

Those travelling are advised to travel the day before or after and to only travel on this route on Sunday if absolutely necessary.