Five and a half month old leap?

My daughter has never slept through the night ... she’ll be 6 months old in 2 weeks. I have no idea what happened ... she’s been sleeping better at least 5 hour stretches because she’s been sleeping on her belly. She’s been going on her belly by herself she knows how to roll so I let her. Well now last night she was up every hour. Wouldn’t sleep on her belly at all. Last time she woke. Up like this every hour was during the four month regression which was brutal. Could this be another leap?? It seems like she forgot how to get to her belly or something I don’t get it at all. She’s extremely fussy. Has this happened to anyone else around this age? I don’t understand why she’s suddenly not sleeping on her belly.