BG, I have combined working and BFing/expressing successfully twice now. I think at around 7 months old my DD was having 2 or 3 X 120ml bottles of EBM while I was at work (I can't remember exactly ). And I would send a sippy cup of water as well as some solids along too.

I could never make up the amount of EBM I needed for daycare while I was at work. I would always have to do some extra expressing (usually at night after she had gone to bed) of 60ml here and there to make up the amount required.

My two have always been able to adapt to being away from me, feeding more when I was around and EBM from a bottle so I guess I've been lucky. I hope it works well for you and your darling E too. It does sound like you have everything well organised and under control.

Wishing you all the very best (it can be a very emotional time).