Call Sonic and tell them to inform AT&T you want another RG. Specify the BGW-210.
Has anyone successfully done this? AT&T customers themselves cannot guarantee delivery of a BGW-210. AT&T Call support indicates that yes, they can ship a replacement router, and it will definitely be a BGW-210. Then another Pace shows up in the mail.
It'd be great if Sonic could somehow backdoor things such that a BGW-210 would be delivered by AT&T, but I've seen no evidence this is the case.
Requesting a truck roll from AT&T seems to be the only way to get it done.