How were you pushed back to the line anymore than anyone else? I had a pre-order that was repeatedly delayed. I cancelled it and got on in store using the reservation system that was available at the time, followed the rules and got my iPhone Plus. EVERYONE was pushed to the back of the line here dude (or dudette).
I WAS unhappy that my phone was pushed to the back of the line, but I decided to do something about it rather than bully people online that got what they wanted first.
I don't get why these IUP people think they should get special treatment. No one has explained this 'privilege' that they think they own.
Like you, I got a delivery date later than I wanted. Like you, I went looking for a solution - an available iPhone 7 Plus, and bought it.
Why can't they do likewise? Instead, all they can do is sit back cry 'foul'.