IMO and IME as well children NEED a consistent meal / sleep schedule in order to be able to learn to self regulate their body .... if some days they are kept up later at night allowed to sleep in and than fed later and the next day they are dragged out of bed early, offered food earlier as a result in so forth their body has no CLUE how to regulate hunger and sleep cues and therefore to truly relax in order to fall asleep!

And yes as Sunnydays mentioned this is exactly why I do not offer 'half day / flex time' programs because and so forth for INFANTS because it goes against everything I believe young children need in order to thrive ... as they grow and have a better grasp of self regulation and a better understanding of how life works than you can start getting more flexible with their sleep/meal time offerings but when WE we should be consistent with having access to meals and naps until they have learned to self regulate those themselves!