I suppose it doesn't matter what branch you're in. You hurry up and wait, then suddenly, things change and you got a week to react.
I am glad to see you are looking at this as a three way win-win-win. Would you be happy in CO if xw continued on her self-exploration path and it didn't lead to you? What will make you most happy? You should take your son's desires into account of course. But if one of them wants to be in CO, doesn't he have the option to stay with his mother? I don't know. That sure is a tough decision. And a week isn't a lot of time to do it in!