Had my model 3 AWD serviced this week and while I was waiting for my car, I went ahead and asked several tesla employees from different departments about the hardware comparison (motors, inverters, etc) between the AWD and the performance model and therefore the possibility to purchase a software upgrade\unlock from AWD to performance post purchase.
the answers were all over the place.
Sales woman: "No, the configuration you bought is set in stone, no changes possible. Why would they make two different car versions then?"
Sales guy: "No, the performance model has a bigger front motor with more coils" (wtf)
Service guy: "probably, they share the same hardware so I wouldn't be surprised if they unlocked it as they did for ludicrous mode, time will tell and you will know before we do"
Mechanic : "Honestly, I don't know, I think it's the same hardware, it would make sense that it is"