Hi Mary!! It's fantastic to hear that she's doing so well! I wonder if the disturbed naps are from a bit of overtiredness, she may be having a bit more A time than she can handle. 30 mins wake-ups are a classic sign of OT.
At 3 months old, most can handle just about 1hr 20-30mins MAXIMUM, and often the first A time of the day needs to be shorter than the rest. So from a 9am wake up she'd need to be going down for her first nap by about 10.15. Then if she takes a longer nap (1.5hrs plus) she should be able to hand 1hr 20-30 mins for the rest of the day.
Remember, if she takes short naps, the next A time needs to be kept shorter to compensate.
Just one more observation, your day runs 9-9pm? I know you know this, but as she gets older her bedtime will move later, so bear that in mind!
Hope something here is helpful,
anna
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