I note:
Other Changes
^ Service alteration to Chippenham, Melksham, Westbury
services
I tried out Melksham to Swindon and back on 28th December ....
07:17 to Melksham, change at Chippenham (07:29 to 07:55) and into Swindon at 08:13
Return at 17:32 (a sensible time!) change Chippenham (17:45 to 18:44) and Melksham at 18:54
or
Return at 18:34 / 18:49 to 19:44 at Chippenham / 19:54 into Melksham.