Toddler taking HOURS to fall asleep!

Hi all. I've posted about this before but wanted to take another stab at it, see if I can get some other people who have been through this.2 years 8 months. Bright, aware. So gets easily overstimulated.No juice, no sweets.When everything is good, she goes to bed around 7ish usually asleep around half hour later. Wakes around 7 give or take half hour.Currently and for the past month at least: she's been getting really overtired and manic crazy in the evening. We know sleep begets sleep and have had luck with putting her to bed earlier for a few nights. But not now.Tonight : it's been three hours and she's still awake. Thankfully she's just recently gotten better at self regulating so at least she's not resisting or crying out. She's wriggling and taking and singing. I know a lot of people will say if she's not upset then either nothing to worry about or it means she's already having enough sleep (so drop the nap or shorten it). But that's it - she's wrecked by the end of the day. As soon as we start doing wind down she's rubbing her eyes etc. We know she's overtired because she starts getting really cranky in the afternoon and a little throughout the day. Yelling, being contrary etc. Normally that's quite rare.We do bed bath books style wind down. We rub her back and tell her stories in the dark for ten minutes. We don't repeatedly go in or anything like that. We are pretty strict with our routine and it's always worked great.About a month ago she missed a few naps in a row due to circumstances beyond our control and since then her level of rest has been tenuous at best. She'll make up a little one day then take three hours to go to sleep the next. We've run out of tricks and I'm worried that what happened last time (meltdowns many times a day and super early wake ups) will start happening again.Thanks all! via /r/Parenting http://ift.tt/2hfuFck