I know he is a respected vendor, and it has been known/heard around the communities that he has or had been ill. He may be behind in orders due to this and possible may be still be ill.
I would send him another email notifying him of the date you are moving, so if by chance he can't get the order out to you to get to your current address he will have your new one on record. Ask him to just confirm that he has received this information so you won't have to worry that your wheel is being shipped to your old address after you move. Maybe he'll just hold off after you move if he has it made and ready to make sure you get it.