I doubt it - they never really cared about a little thing like Causality.
They would have picked up 1971 with some brief explanation of what had gone on for the months the show had been in 1841PT. And as with Quentin's haunting, some characters would have probably remembered Gerard and Daphne while other wouldn't. The big question is how they were planning to bring Angelique back because they definitely intended to. Would she have been a ghost? Flesh and Blood? A witch? Or a mortal? And we could probably speculate for days on all that and possibly never hit on what they would have actually done...