XBee S2 Backup Coordinator

Hello guys! I think I'm back into further checking out XBee's capabilities.

Is it entirely possible to assign a router device to become the backup coordinator after the original coordinator has failed (due to power loss and etc.)? Furthermore, if the original coordinator is restored, is it also possible to return the "role" of coordinator to the original one and the acting coordinator back to being a router device? How?

Is there any knowledge you can share on this? Thank you. I don't think I may need links or sources for this question though. It's just an idea though.