3 to 2 naps

Hello, my LO is 8 months old. And most days the 3rd nap is impossible to fit in the schedulle. But i am worried that with only 2 naps she doesnt have enough awake time. She currently stays awake 2h40 in the morning and 3 hours between the other 2 naps. Her naps are more that 1h30 long. Sleeps 10h30 in the night no matter what time goes to bed. How many naps do your LO takes? How did you know it as time to drop the 3rd nap? How did the transition go?