Ok 1. Only about 3 or 4 people have said book an appointment and I do believe a dozen is 12. Unless you mean a bakers dozen then it's 13, and I have said it hard to get appointments.
2 I have had a Mac exchanged for a new model and didn't know if it works the same with iPhones
And 3 yes the Belfast Victoria square store and I have gone through the app and the website and both are saying there are no appointments available.
How on earth are you getting three? There are more people on page one that have told you "no" than that, which is what I am referring to.... Anyway, I'm still astounded that you've gone on for this long, but I do applaud your gumption. Ask the Apple Store if they'll upgrade you and see what you say. Point out to them you've done it before with your Mac. What do we know?
This entire thread reads as justification as to why you think you should be able to bring in your damaged (though I do trust this may not be your fault) phone and expect the next newest device be offered to you. I'm unclear why you expect this and I am unclear why we are even having this discussion. Literally nothing we say is going to change what Apple tells you. "But this one guy on Mac rumors said they didn't for him", is not going to get someone at the Apple Store to do anything more for you than they're required to do.
Anyway, I think we have covered this to the point of nausea. Report back with what you do, if you wish, and I truly wish you the best of luck, despite feeling your justifications are not so justifiable.