Hi EBM,
My main suggestion is not to get too worried about it. A couple of months ago I was in the same situation - return to work looming, baby absolutely refusing bottle, and to top it all he's allergic to milk so has to have a special formula that tastes grim so who could have blamed him for turning it down!
Anyway here we are, back at work, settled at nursery, and positively opening mouth and grabbing for bottle, downing 8oz in about 2mins, 3 times a day! He is still a bit funny sometimes, doesn't always take milk at nursery, but I have nearly wound the bf down to nothing now, he gets bottle in the morning and bottle before breast in the evening (plus plenty of solids now).
SO, I hear you asking, how did you get there? Basically keep on trying and be open-minded! I did have quite a determined period of trying where I offered the bottle first at all the daytime feeds (kept morning/night calm & cuddly with breast only). But I didn't push it or leave him to get really upset (tried that a couple of times but made no diff). I tried some different cups as well as the bottle and I tried both formula and ebm (and mixture of both).
One great breakthrough was when he realised that the bottle could fill him up ie. make him feel better when he was uncomfortable (hungry). But of course he only found that after lots of attempts. Sometimes it seemed there was never a right time for the bottle - he was either too full, too hungry or too tired. But that's why you just have to keep on offering it. And accept you will throw lots away!
I did express a bit but never got huge quantities. I know you said you don't want the hassle of expressing - but when my ds started nursery he would take ebm fairly reliably but was still funny about formula and not taking water or much solids. So I gave them a backup bottle of ebm every day for about 4 weeks just to reassure me/them in case he got very upset. They only used it a few times and his solids intake upped quite well so now it's not so important if he doesn't take much milk during the day.
I'm sorry for waffling on - I do hope this gives you some hope! As Aloha says, your dd will change so much in these two months you'll look back and wonder why you were worried! If I can help any more please feel free to CAT me.