I asked First

At present, many visitors to our business arrive in Melksham on the 09:12 train, which has a connection off the 07:45 from Paddington.  Reading the new timetable, it appears that there is no connection from London into Melksham until the London departure at 17:00, arriving at 18:38.

If the proposed timetable is brought into effect, what alternative arrangements will be made for people coming IN to Melksham at around 09:00 and wishing to LEAVE at around 17:00?  Will you be providing a rail replacement bus service, or will the local First bus company modify their route 234 to serve the staton at Chippenham and provide connections?

They have replied

I am happy to inform you that we are currently in discussions with First Bus with regards to extending the 231 and 234 to Chippenham and we hope that this can be initiated at the earliest opportunity.

Whatever the train service outcome, it WOULD be sensible integrated transport for the 234 bus in Chippenham to routinely serve the railway station.

It would also be more than sensible for the X71, X72 and 234 buses in Melksham to call at the station - at least the service that runs before and after each of the 10 (cuurent) or 4 (proposed) trains calls.   The new road link from the Bloors development near McDonalds will allow these routes to pass by the station without the need to turn around there.