Originally Posted by
allturnleft
Trying to book an open Jaw ticket to Australia. I have found there are far more options when booking through third party sites. My concern is that by using these sites you will loose all your MMB options. Do any of these sites allow one world seat reservations (e.g BA or CX) or allow later upgrades with cash?
Once you have the PNR locator you can use that on BA.com to manage some aspects of the reservation, that includes seating. But it generally excludes cash upgrades, and tends to make UuA upgrades difficult to impossible.
If you find out the fare basis on these agency websites, it is worth ringing BA. BA.com has a simpllified interface which removes options that you may then find on a travel agency site. An experienced BA agent may find the same fare for you. Not guaranteed, but worth a call.