I have noticed the last couple weeks she will wake up crying/unhappy around 8.30pm and need a quick resettle but goes back to sleep easily. We were unsure if its nightmares?? or as a result of OT from during the day.
Probably OT at BT. Sometimes you just have to roll with this for a little while as the lesser of the potential issues with this transition.
It is possible to do a super short CN (eg. 15-20min) in the morning and cross fingers for a long PM nap. If you have strong enoguh sleep cues and she'll go to sleep when she's put in her crib, that might work though its tricky to get the right timing as children this age are so variable in what's good for them.
I'm of the opinion that a good solid night sleep which you're now achieving is much better than 2 naps if you've got to choose between the two.
Have you had any luck resettling the 1hr naps in the last few days? They can be OT naps at this stage of the game. I wonder have you considered alternating one and two nap days?