Hey T.,
Im a preschool teacher as well as a mother to a 3yr old little girl. From my personal experience, I noticed that anytime we didnt stick to my daughters schedule of a daily nap from 2:30-4:30 and bed by 8:30 (which she would sleep untill 7:30 the next morning ) she would be cranky, over tired or if she got later naps she wouldnt go to bed untill much later.
In my opinion with working with 2-5 year olds, they strive off of schedules. They like routine and like to know what comes next. Anytime we switch it up a little, I have seen kids have little melt downs.
ALSO, remember with age they might need a shorter nap. The two year olds at our school tend to sleep from 1-3 getting a good two hour nap but the 4-5 year olds who are getting ready for Kindergarten tend to only need 45-minutes to an hour of rest time. some are completely grown out of naps and just rest for a little while.
So, my advice is to just go with what works for her. make sure she gets a nice nap of at least an hour but if its past her usual nap time I would try to keep her up ( play games with her, have her help you around the house) then get her fed for dinner,bath and bed by 8:00 and im sure she will pass right out!!
GOOD LUCK!