The official club website (checked just now) says:
“Stadium Capacity: 6,909 *subject to review for specific fixtures”
The Echo (i.e. the Gloucesterlive website, again checked just now) says:
“Cheltenham Town FC were formed in 1887. The Robins play in the 7,066-capacity Completely-Suzuki Stadium and ply their trade in SkyBet League One.”
But since they don’t realise Suzuki are no longer the sponsors, nor that we got relegated from League One more than a year ago, I think we can treat that figure of 7,066 (like everything they publish - sorry, JP) as “unreliable”
And today’s match report (again from the official club website) says:
ATTENDANCE: 6,677 (1050 from Leicester)
We have heard at times that TV coverage may reduce the maximum capacity - but the cameras are normally pitchside (and on a gantry above the roof at the Prestbury Road end) so I’m not clear why that should reduce capacity for spectators.