New False Starts

8 months old, sleep trained, 2 nap schedule (3/4/3 or sometimes 3/3.5/3.5 LO really struggles with 4 hours for the last WW), all of a sudden false starts every night for the last 2 weeks. In the last two weeks LO also started sitting up from belly, crawling, standing in crib, and second tooth coming in. What do I do about the false starts?