As a hypothetical trip, I would like to do:
Perth (PER) - Abu Dhabi (AUH) - London (LHR)
Dublin (DUB) - Abu Dhabi (AUH) - Perth (PER)
Flying First Apartment for the AUH - LHR leg only, redeeming through Velocity points.
In order to do this, would you need to book the economy and 1st Class flights separately, or could you book it all as economy and upgrade the LHR leg? Would it be much better to make it a return to/from LHR, rather than departing from a different country?
Thanks for any help guys!