FGW policy change on Advance Singles?

[Green Janner]

I regularly use the Saturday 19.42 Plymouth to Paddington via Bristol.
Advance Singles have always been available on what is normally a little-used HST service - at least until Bath Spa.
However, after 20th February, Advance Singles and First Advance Singles appear to have been withdrawn. Currently FGW are selling Advance tickets until 31st March - but this service has nil availability on 27th Feb, 6th March, 20th March & 27th March. The service has a partial bus substitution on 13th March due to maintenance works.
Have I missed something? Thanks in advance.

 

[devon_metro]

Weekend booking horizons are different. There is normally also considerable engineering. I know the line through Dawlish will be closed over weekends so perhaps that will affect it.