Yeah, with how quick all the show's last episodes went chronologically, this finale (plus the last couple eps) easily fits in the gap between the beginning of IW and when Thanos bumps "Sprinkle Me" at the end of the film. Plus, since the next series isn't debuting until after A4 is in theaters, they can do their own thing for S6 with any ramifications possibly rectified by then.
Such a great finale. Even if the series ended here, it would have been pitch perfect as well. Glad we got more though.
Odd thing to be good at, but this series does do send-offs very well (remembering the Hunter/Bobbi send-off).