I was able to transfer her to the hammock on her back without disturbing her once we went to bed, so we might get away with it in the evening. Fx! Little things certainly like to keep us guessing.
My baby sounds exactly like yours! Transferring worked for us right up til 9 months, day sleeps were short or worn, and we just rolled with that. Once I succumbed to tummy sleeping at night, we had 11 hour sleep throughs, and 90 minute day naps - HUGE in this house.

Good luck!