I should have added that the place that obviously could benefit from a later service on that screen is Melksham.
Yes ... and no (or, rather, not yet). In May, the last Monday to Friday train moved from 20:06 to 21:16 off Westbury, and from 20:45 to 22:30 off Swindon, with both new trains doing well. And then in September, for the first time for many years we have a Winter Saturday train later than the 18:35 - again bedding in very well (actually very well indeed!). We can now claim an "all day, every day" service all year. But the service is both thin and unreliable, and that view is tacitly acknowledged by
GWR▸ With an increase from a thin to an appropriate (hourly) service
which runs reliably, passenger numbers using the service should rise fourfold (for twice the number of trains) and that would include a Westbury departure perhaps as late as 23:00, with a 23:50 service back from Swindon. But whilst I might have hinted to Uncle Rishi's troops at times in the past that I would like this, he didn't include it in his largess on the cancellation of the northern leg of
HS2▸ , so we must keep asking.