How much EBM for almost 10 month old?

[BreastmilkDoesAFabLatte]

I'm going to be in hospital next week, and won't be able to feed DD for at least a few days. I'm trying to express milk in preparation, but have no idea how much she needs. DD is tiny for her age (though we're a very small family) but extremely energetic and active. She BFs 4-5 times per 24 hours (alongside BLW and throwing mashed potato at the cat), but I have no idea how much she takes at each feed.

How much should I be expressing?

I am guessing roughly 6oz per feed, roughly 24oz per day? Maybe a little less if she's eating lots of solids? For 3 days express a lot!

Oh dear. I should have started this earlier [cow emoticon]