Emma has been away from Piper for about three weeks. Silver is not mating with her, and I haven't seen her neat anything that resembles nesting material. I am trying hard to keep them on fourteen our nights, although I may slip up here and there.

This afternoon I saw her on the floor of the cage, backed up to the back wall, with her tail right up in the air.

Do you think this means she's already producing an egg?

I got her out of the cage and have been trying to keep her busy.

It doesn't necessarily mean that she's producing an egg but it IS nesting behavior. Keep on keeping her away from nestlike areas, but at the same time handle her carefully in case she does have an egg inside.