1) You can scale it back, although with how long Cider goes any amount of flavors developed by overpitching yeast will have disappeared. So I say, if you are aquainted with the fermenting process (experienced) then scale back, otherwise pitch the whole thing.
2) In general you want conditioning temps to remain stable. However, work with what you have. As long as you aren't riding up into the 60's, 70's etc then you'll be fine. It can affect long term storage though (although you have to put this into perspective, like are you planning on aging the cider for 5 years? )
3) I don't. I just wait until most of the sediment has dropped out and then bottle. More drops out in bottling but I have never had any issues as a result of this.
4) Yes. Same as #2 really.
5) You can wait several months no problem. Bulk conditioning vs. bottle conditioning are always a debatable topic. I bottle condition most things, except for very high gravity brews.
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