I also have a 27 month old and I'm finding her sleep a bit tricky right now, so you're not alone!
I guess the first thing is to of course rule out any physical factors that may be disturbing her--illness, teething, temperature of her room--and any major change in her routine or development.
Looking at your routine--I have to say it's not that different from my dd's except my dd's is about an hour later--she fell asleep at 8:45 last night and was up to 6:30, although her nap was from about 1-2:30--oh, and she also usually cries out around the same time each night--2:30!
I think some lo's at this age start entering that awkward phase where they still need to nap but it can interfere with night sleep causing them to fall asleep later than what is ideal for them and that's when the NW's and early wakeups start. Given her age I don't think you can get rid of all the variability but I would first try napping her at the earliest time she would be willing to nap so that there is a little more A time between nap wakeup and bed time so she might go down a bit earlier. If that doesn't help you could try shortening her nap. It looks like she still gets about 2 hours, and I think most lo's around this age start moving toward a nap of 1.5 hours. You may want to set a time--like 2:30-- which you will always waken her.
Good luck and if you find something else that works let me know!
