Went back just 2 weeks ago(he was 5 months).
He had a few days of difficulty adjusting to daycare, but they were able to feed him just fine. One day I even miscalculated his milk so they had to give formula. Not thrilled about that, but it was my own fault. He'd had a few bottles before with sitters so we weren't too worried about bottles. They have a nursing nook there so a few times I've been able to go on my lunch break and feed him.
Mostly I was worried about sleep because we bedshare. But they said it was actually quite simple to get him into his crib.
Honestly it makes me a little sad that he is alright with a bottle.