It's the usual crowd year in, year out. FOM (who do the logistics) work with a handful of carriers. Screw-up and they'll drop you though.
Working with FOM in my experience is an L/Ms dream. These guys (AW and believe his son had the same initials) know all variations of 74F maindeck configs you can imagine. They make their own loadplans, rarely need changing (perhaps a tweak here or there to your tastes/odd performance issue...).
March again already ... vroom