Congrats on your pregnancy! For newborn AIOs, I'd recommend having 20 or so. My newborn pooped so often during the first few weeks so having at least 20 (we used disposables at night) helped me from washing them every day.
I'd also recommend a stash of 20 or so pockets/AIOs, especially if you're doing daycare. We send 4-5 diapers/day (still using disposables at night) and that means I can wash every 2 days with plenty of time to air-dry in between.
***TW*** RAD born 6/2015 | mc at 7 weeks 9/2016 | rainbow baby RHD born 9/2017
I have 21 and that was too few for washing every other day. I'd usually have to use at least one or two disposables for the last couple night changes. FWIW, I do have a longer wash cycle than most people in that I wash them in the evening and then dry them overnight on an indoor rack before drying them the last bit in the dryer the next morning. But honestly, I feel that even if I just dried them in the dryer, 20 would be almost too few. I don't like having just one left at the end of the day or putting the last one on her as the others are still in the dryer. I want a bit more of a margin than that. I'd prefer having 24 or, with my wash system, 26-28.
I've recently switched to washing every day and a half and that's working better for me.
Re: Due November, how big of a stash?
I'd also recommend a stash of 20 or so pockets/AIOs, especially if you're doing daycare. We send 4-5 diapers/day (still using disposables at night) and that means I can wash every 2 days with plenty of time to air-dry in between.
RAD born 6/2015 | mc at 7 weeks 9/2016 | rainbow baby RHD born 9/2017
I've recently switched to washing every day and a half and that's working better for me.
ETA by that I mean any combination of AIOS, pockets, prefolds, fitteds or flats.