Hi poppet. It sounds like you're doing a really wonderful job with the expressing. I remember how much work it was when I had DD, who was dc1. It must be such an undertaking with a toddler.
The midwives/nurses also offered me different advice when I was trying to establish BFing with DD. There was one midwife who was the specialist feeding coordinator so rightly or wrongly I tended to listen to her. Do you have anybody like that on your SCBU?
Unlike some other staff, the specialist lady said it was ok for me to let dd nuzzle in at my boob, and lick the milk if there was any dripping. Some of the others said she had to be either feeding or else I should remove her from the boob. But the specialist said that it was good for DD to associate the boob with comfort, and to get the idea milk came from there.
Anyway, on the establishing point...
At the time DD was on SCBU the staff bottle fed babies (with mums permission only) if they seemed awake enough at feed time. But they were just about to all be trained in cup feeding, with the intention that they could cup feed those babies who mums were hoping to bf. Again there was disagreement between the staff over whether bottle feeding could cause nipple confusion, bottle preference etc.
There was one mum on our ward who was determined to bf so wouldn't allow the nurses to bottle feed. She had school age children and was in hospital for all the feeds during the school day and at least one evening one. Then she came and roomed in at hospital for I think three nights, and the hospital ensured the baby was thriving on BFing before letting them home.
I was more fussed about getting DD home than about getting her BFing. So I let them give her bottles. And actually I even gave her some bottles myself. She was my first child and I just didn't know how fabulous BFing was, I think I might have a different attitude now.
Anyway, we got DD home on bottles of expressed milk. I kept offering her the boob but not every feed by any means. She was so sleepy and I also if in honest quite hated the feeling of rejection when she looked at my boob with her mouth pursed closed.
I've had a look at her records and she was just over 37 weeks gestation and weighed 4lb 10 when she finally 'got' BFing. I guess we were lucky that she was getting weighed twice a week to check she was thriving. So basically one feed she latched on and fed from me. After that I totally breastfed (also had to express a bit to relieve pressure). I knew I was producing enough milk for her so I just went with it.
A few things we did which may help was
1 I took her off the hospital bottles, which were really just dripping milk into her mouth. We went onto tommee tippee closer to nature which she needed to open her mouth to take, and actually make an effort to get the milk out.
2 her milk in bottles was always room temperature, Woth the idea that she would prefer milk from my boob as it was warm.
3 I fed her her bottle with her kind of sitting on my lap facing me, not in the snuggly cradle position, again so that she would hopefully prefer boob.
I hope some of that is helpful. All the best. It really does sound like you're doing a fabulous job.