I'll tell you my experience - then I'm not saying what definately happens to everyone but you'll at least be aware.
DS was born by CS at 37+3, he was breech but that had nothing to do with the diabetes! He was hungry v soon after being born and I was adamant that I wanted to BF, so they tried to latch him on but neither of us had a clue, and they gave him some formula from a syringe. He was also given some formula from a cup a while later. Not long after being taken down to the ward someone came down from SCBU to test his blood sugar. She gave him some sugar solution first as it acts like a painkiller for newborns. It was just about what they wanted it to be so left him for a while, then when they came and tested him again it had dropped so they took him up to SCBU to be tube fed hourly. Basically the baby is born with their own insulin, plus their 'share' of the insulin that you've injected, but are no longer getting their share of your sugar through the cord, so need regular top ups to stop their sugar dropping too far. They told me that if it did drop too far, he could get brain damage. If you'd like to BF, make sure that you tell everyone so that they don't try to top up with a bottle. He was up there for a couple of days I think (morphine made it all a bit hazy!) and then they said that my insulin had worked its way out of his system and he could come down onto the ward with me. While he was up on SCBU the MWs helped me try to express some colostrum into a syringe, and that was sent up to DS and they just squirted it into his mouth!
BF was difficult, as he'd had a couple of lovely days where he didn't even need to wake up to get fed, and had gotten lazy! I was expressing with a hospital pump, and every 2/3 hours I was trying to get him to take some from me, then cup feeding him some EBM from the last time I expressed that was in the fridge on the ward, then expressed for next time. That was difficult too because I had to feed him every 2 or 3 hours, he didn't get a chance to get hungry and want to suck. He/we finally got the hang of it on about day 5, and we would have been allowed home then but he developed jaundice somewhere along the way, and we had to wait for another blood test for him to say that that hadn't gotten any worse before we were allowed home. We went home at lunchtime-ish on day 6. He'd been born at 1:04am on day 1 (obviously!)
Most of the staff at Warrington hospital were super-lovely, there was just the odd MW who didn't help at all (sitting cup feeding DS so that I could eat my lunch, saying 'oh he's not taking it, he'd take it from a teat I know he would' even after she'd watched me struggle and struggle with trying to BF. I knew he didn't actually want it, because I'd had to pretty much force feed him from a cup only a couple of hours ago. Very frustrating, and I'm still not sure at what point the extra insulin is really all gone, and why I had to make him feed so frequently.
If you have any questions at all, just shout! We go to a group at the westy sure start centre on monday mornings if you ever want to meet for a coffee and chat about it.