Prior to starting daycare at 9 weeks, my DD was sleeping 4-5 hour stretches at night without eating, fairly regularly. Five weeks ago she started daycare and like all babies, had a hard time napping. She still struggles. So we've instructed them not to wake her to eat since she had been napping so little. She started going 4-5 hour stretches at daycare without eating, but still eating the same amount during the day. Almost immediately, she stopped her 4-5 hour stretches at night and we haven't seen a 4 hour stretch for 5 weeks.
I wanted to give it some time, thinking things might change and it could be just a phase. But five weeks and feeding her every 2-3 hours at night still is getting super exhausting, especially being back at work.

She does have reflux and is treated for it. She's also on AR formula and was never breastfed.

Any suggestions? Is the only solution to have daycare wake her every 3 hours to feed her? Or is it that she's maybe overtired at night and not necessarily hungry?