As long as you check-in on Wednesday, you will get your Wednesday Tent camping spot. If you arrive after Wednesday, you will lose this spot and will be placed with the rest of general tent camping.
If part of your group arrives after Wednesday, they can still camp with you in your Wednesday premier spot (as long as you checked in on-time). Simply have the late-arrivals purchase an overnight parking pass for their car. Then, there's a shuttle from overnight parking that can drop them off at the Hub near Wednesday premier camping.