Yes, as I understand it/have had it explained to me, you need to have booked a minimum of Group C (mid-sized) to use Gold Choice, and it has to be the original rental, not a replacement/swap on an existing RA.

What that means is that as Pres Circle, you have to see what they allocated (which should be the "guaranteed" one class upgrade) and if you do not like it, you need a conversation with a counter rep to be allocated something else. If they direct you to Gold Choice (which has happened to me), then that's fine, but you cannot assume that you can just take a car from there for free with a Group A or B reservation. It is yet again a reason why you need to think of Gold Choice as the means for getting a "cross-grade" not an "upgrade".