Yes, on a year-to-year basis.
If we find ourselves in a position to trade him later this month, I would probably ask him if he would like the chance to finish the season with a contender and then talk in the off-season.
Yep but better to do as you said: get him there and wait until the next day to activate and play him. Unless you're going to play him the day you activate him.
With the way they have handled guys coming off the IL multiple times this year, they will activate him off the IL, he will be there taking BP, and be out of the starting lineup for some reason.