I have the same problem sometimes, and in this case, I watch her cues even more carefully than I normally do and I make sure to get all the stuff I need doing done (ie feeding, nappy change), and then, I decide whether she seems up for active play like being on her gym or if she seems tired, in which case I go into wind down. I have found that in that case, she falls somewhere in between, as if she had been awake from 6.30 (with the timings you gave) but it's quite irregular, cues much more reliable than clock in that case.
