Have Lego waited to reveal sets on Black Friday before? Seems a strange date for a reveal, it is more for selling, and is launch date for their other big set. So this date doesn't sound right to me. Also too early, it is still only November.
It is true their are many Police stations sets in the City theme, but none if you only buy from the modular line. Does the town need a Police Station? it has a private detective. Maybe a small police house for the local bobby. I remember images of a Police Station circulating before, and it turned out to be this one from rebrickable
LEGO MOC Modular Police Station by brick_monster | Rebrickable - Build with LEGO