This is the place where Stones fans can advertise anything for sale, wanted, trade or whatever, from fan to fan. Advertisements are for free. To see the old ads go here.
I found this following one on the HotWacks site for 1972 Pittsburgh show
'On compact it was released as An American Affair (VGP 083) that had Sweet Virginia coming from Ft.Worth 1972 2nd concert, replaced with the original version on The Royal Dragon (VGP 083)'
My opinion = there is no SBD version of Sweet Virginia from Pittsburgh available, only AUD. So I think the claim is false. Also, they (obviously) sound like the same version to me, which I believe to be 2nd show from Ft Worth (compared to the AUD version on VGP-133).
blakeeik is right, there is no MB (mixing board - as i call it) available from 22.7.72. the version on An American Affair (VGP 083) is identical with SV on Fort Worth Express(VGP-205), latter however in far better sound quality