Originally Posted by
JayKiwi
Tried this recently, and it was a flat no. Linking people together on the same long haul sector, no problem. Linking dom and Int legs on separate PNRs, no.
Yes they won't link standalone and intl flights (but will interline bags if you're Elite), but the OP hasn't booked the domestic sector though.
They should (well they can, but the big question is whether they will) be able to add a new domestic flight to the existing intl booking, but the question is just how much they'll want for this as it'll very likely result in the whole ticket having to be reissued.