Hi
Well done on successful sleep training
I would imagine that even though you don't feel her A time needs extending, she isn't quite tired enough to see herself through that sleep transition into the next cycle. Moving into another sleep cycle when being held or shush/patted or when given a dummy is one thing but being tired enough to do it alone is a little different. I would be inclined to try a 3hr A time.
It may also be that whilst she is now falling to sleep independently (no prop since sleep training) you have not trained her to stay asleep and self settle mid nap. This is still part of sleep training. You shush/patting during nap 1 to help her re-settle is part of that training, you are telling her it is still sleep time. After a few days (and if on the right A time) she should become accustomed to the idea of having a long nap the way you are showing/telling her to. This is one of the W2S (wake to sleep) methods, you can read about here:
How do I address habitual wakings? (wake-to-sleep and other methods)Usually you would do it for 3 days and then hold off to see what happens, this is so you don't end up stuck in the room for every nap day in day out for the foreseeable future.
Whilst you can certainly continue to use the dummy to extend nap 2, I would probably advise not to just because you have already dropped that prop so it seems more logical to keep moving forward. I really do think an increased A time would help, and you could use the shush/pat W2S for a few days to see how she settles into it. It's possible to just increase the second A time if you don't want to extend both in one go, that way she will be more tired for nap 2 where you are having difficulty extending.
hope this helps
