I suspect there may have been an element of that going on, in that the travel agent found availability on the return connection to NCL which wasn't actually available on the BA website (which is good, because it gets me home a few hours earlier). I suspect overall though it's the promotion which is causing the general effect, because just playing with random bookings to JFK it was doing domestic business for some flights and economy for others, and ditto for other destinations, depending on fare bucket of the long haul sector.

I did have a very vague memory of reading something on here about domestic connections in business, I just couldn't remember the slightest detail hence asking the question. I'm pretty sure it was that promotion which must have been causing the vague ringing of bells.

BB - I'm in E for both legs of LHR-DFW and I for both the domestic connections. Not sure if this helps prove or disprove the theory! Edit - Looks entirely consistent with the promotion rules so more evidence in favour of the theory.