I was delighed to pick up a new ranger and rover leaftet at Trowbridge station at lunchtime today - and with a useful map in the back showing the lines covered by the rovers (but not by the rangers). The map is labelled "Information correct as of May 2019" and is (or was), therefore, definitive; it does not say "errors and omissions excepted" or any other disclaimer.
I note:
The Freedom on Devon and Cornwall Rover is NOT valid from Exeter St. Davids via Exeter Central to either Exmouth or Axminster.
The Freedom of Severn and Solent is not valid on direct trains from Bristol Parkway to Newport
The Freedom of the South West and Freedom of Severn and Solent tickets are valid to Cheltenham Spa and stations to Malvern, but only via Gloucester and not on trains that avoid that city.
The Great West Way tickets are no longer valid from Swindon to Bristol Temple Meads on services that run via Bristol Parkway, nor to Frome. However, they have additonal validity from Reading to Basingstoke
The Freedom of Severn and Solent (but not the Freedom of the South West) includes Southampton to Weymouth (including Lymington Pier and Swanage), direct trains from Romsey to Eastleigh, and services from Salisbury and Yeovil Pen Mill to Axminster.