Originally Posted by
PLeblond
Perhaps it's mainly a charter for BAH and BA is willing to sell seats but at a much higher price to keep space for BAH. I've seen the same on AC Vacations for Caribbean Routes.
BAH seem to take flights from the same place as booking yourself, so I don't see them being cheaper for this flight.
Annoyingly it does mean you can't get the DOH flights come up instead instead of the BA one unless you use the multi-city tool.