So. Amazingly. Hard. To leave her alone!
I set up a large dog crate in the coop with a cardboard nestbox in it and some food and water. I would really hate for her to get mad and give up the hatch at this point because I moved her, so I will leave her be until someone hatches under the assumption that she might leave a nest of eggs, but if there are peepers there calling her, she will probably stay with them (and hey, at that point I just stuff them in the brooder anyway, so no loss).
So I'll wait for at least one to hatch before moving her , baby, and remaining eggs to the dog crate.
The nest box she is in now is a foot off the ground so I am afraid of babies nose diving out of it!
Oh, and she is a Polish, so I am amazed she made it to day 21 at all!