That's a good question, anon. Normally I would say I think they will be filming 9.07 starting this week and leave it at that. But that was before we learned that 9.07 appears to be a stand-alone, non-Blacklister ep thanks to u/lyokohwk on Reddit. Based on a couple of things I've seen that I thought were for 9.07 that now may be for 9.08, I wonder if they are going to film 9.07 in tandem with 9.08 like they did with the Anne and Misere eps last season. Time will tell I guess. At the moment, I have no further info and as you say, with those eps not airing until the new year, we may be waiting a bit.