I don't think you understand how it worked. IUP members were shunted off into a separate ordering system where we could not order at all. No first come first serve, no wait a few weeks for the phone you want, the system didn't allow us to place any order. We're the last served, we can't order online.
Unlike normal customers we weren't offered a full lineup of choices, only what a local store was going to have the first Friday, which in my case initially didn't include any 256GB phones and quickly didn't include any phones for my carrier. (I guess I could have ordered a 32GB rose gold sprint phone, but it wouldn't have done me any good.) With no valid choice on the page we were stuck, that was it, there was no way for to place an order. IUP members were uniquely locked out of the pre-order, probably (I'm guessing) because of a glitch in the ordering system. Or maybe because someone really never thought this through?
Either way, Apple has a long way to go to make this up to customers that paid to upgrade after a year, and then were locked out of upgrading. Maybe a new IUP only pre-order? Maybe waive monthly IUP payments until they catch up? I'm not sure really what they can do now to salvage the program, but they need to come up with something quick. You'd have to be a fool to sign up for IUP today.