This somewhat resonates with me just now. I'm in a not altogether dissimilar situation and I'm wondering whether to pursue recourse. It's moderately significant but not super serious so it's a question of balancing the frustration and futility of potentially wasting my time against a comparatively minor gain if I win.

I'm on a DONE4. I specifically booked our DOH-HEL segment as the AY codeshare because that way is supposed to earn over double the Avios points in my BA account than would the (actual) QR flight. When I checked in, however, the BP showed the QR flight number. I went to the service desk at DOH and explained why I wanted the AY flight number on the BP but they claimed it was impossible to do it that way. And now, sure enough, the points have credited to my BA account at the lower QR level rather than the desired AY level. I made the booking with the AA RTW desk and have a 001- ticket. The itinerary / ticket receipt does show the AY fight number for that segment.

The difference in points is 3415 v. 7513 or 4098 x 2 pax = 8196 points in the family account, which is nearly enough for a free shorthaul ticket. Granted, that's not so very very much in the overall scheme of life but (a) I do sometimes get caught up in 'the principle of the thing' and (b) I don't like to feel that I've been done out of something due to me. What do you think, lads? Do I gird up my loins and approach BA about this? Do I actually have a legitimate case to argue?