I meant work hours when you go back
if you're planning to feed her BM in the cup/bottle, you might find you don't need to do as many feeds as you think with the cup. For example, I used to do morning feed, leave, get back by 4pm have a feed, bit of dinner, have another BT feed, so that was still three feeds in the day, iyswim. Means there's less worry about what she's getting from the bottle. I think from what you say you have a few months before you go back?
As regards different bottles and cups, just let her keep trying, they learn new things every week at this age. She'll get it
And remember, if she'll take a bit from the cup or bottle, that's a start! you can build on that.
My LO2 was a totally bottle free baby and was BF to over 2.5 yo, so it's possible. There are a few bottle-free BF working mamas on this forum in fact. So don't freak out about it just yet