22 month old sudden sleep issue

Br

😴 anyone successfully push back a toddlers wake time? For the past couple of weeks, my 22 month old has been waking up at 4am crying. (If she were just playing by herself I would just let her stay). Sometimes acting sleepy, sometimes ready to go for the day. Yesterday she randomly woke up at 7 which was a freaking miracle, but we are back to 4 today. No idea why. She does one nap around noon for 1-3 hours and usually goes down for bed at about 7:30. We have pushed her bedtime back, woke her up from nap after just one hour, etc. None of the schedule changes work much. No changes in room environment or anything. We still have a blackout curtain and sound machine we use daily. She even woke up at 2 and 4 the other night wanting someone to stay with her and rock her or hold her hand. Ughhh. She was always an amazing sleeper, her usual wake time was at least 5:30, which was still early but doable. 6-7am would be ideal though.