London Paddington to Bristol Temple Meads – some trains will be diverted via Bristol Parkway and won’t call at Chippenham or Bath Spa.
Other services will still call at Chippenham but will terminate at Bath Spa, where buses replace trains to Bristol Temple Meads.
Portsmouth Harbour to Cardiff Central – trains will divert after Trowbridge and terminate at Swindon. Change here for South Wales services.
Cardiff Central to Portsmouth Harbour – trains will terminate at Bristol Temple Meads and buses will replace trains to Bath Spa; trains will run from Bath Spa to Westbury; it may be quicker to travel to stations beyond Westbury via Swindon instead.
Westbury or Weymouth to Bristol Temple Meads – trains will terminate at Bath Spa, where replacement buses will run to Bristol Temple Meads.
Please note, South Western Railway train services between London Waterloo and Bristol Temple Meads will also terminate at Bath Spa.