First Great Western have hired a unit from South West Trains on a day to day basis.
It works from Salisbury to Swindon in the early morning, spends most of the day on the Swindon to Cheltenham Spa line , goes to Bristol in the Evening , and then goes home to Salisbury on a Portsmouth working from Bristol T M
Thats how you saw it at Cheltenham , it will be hired for most of the summer. It is not always the same unit , because of maintenace etc .
The week before last I photographed two different units on hire during the week.