Hiya, you may well be on the right thinking track Hun, I agree. Usually changing things up every day just serves to mess up LO's body clock, even though it can be useful in the short term to allow them to CU. Can you try for an 111 am set nap, and if you do can nursery follow suit, so he has consistency
TBH though I wouldn't set BT too late while the EW continues, just in case it actually perpetuates it YK
If you can try and stick with a 13 hour day max.
HTH.x.