Well, the sad news is i've decided to move on to just bottles (of EBM for the most part). Had a hideous weekend where DS started screaming every time he was handed to me to BF, screaming and pulling off during feeds, tears streaming down his face, as well as writhing miserably when we tried to do suck training and I thought that's enough, we're all miserable and it's no longer worth it after 3 months of struggling. Worst bit was DH, who was also near to tears every feed watching the whole thing. We have to do four long haul flights with him in the next three weeks and I just can't face doing this on a plane on top of everything.
I feel quite sad, but now that I'm just expressing, he's actually getting more of my milk as I have more time to pump (and also probably because I'm not in tears all the time). I don't think he was getting much from my breast by the end as he was mostly just sucking at the nipple like it was a bottle unless I kept relatching him (which would make him scream). He never gum-chomped, he just fell off the breast or fed for literally hours (our record = 8 hours straight). Then, after he'd had lots of bottles, he would try to make the latch shallower and feed like my breast was a bottle.
What I am going to do, though, is use the breast for comfort, so let him suckle if he feels like it (and encourage him to) but not rely on it as his food source. We've had a few goes of this and he loves it, especially in the bath - he latches in his not very effective way, suckles a bit then grins happily up at me. So we're getting the bonding without the tears! If this goes well, I'll try latching him better and trying to get him to feed again when we're both calm but if it doesn't work, that's ok.
He's only now, 10 days after the snip, starting to stick his tongue out. It's so annoying that we couldn't have it done earlier. I think he would have adapted faster, developed less bottle preference and wouldn't have been so distressed. So to anyone else thinking about it, just do it!
thanks for all your support and comments, it's really helped and made me certain that if it happens with the next child, we'll have it sorted immediately.