I know this was addressed before, but I couldn't really find anything on the dashboard, and searching for "AA" doesn't work. Anyhow ...

By checking aa.com for saver availability (ORD-DUB), and cross-checking with ba.com, I located a date when AA had availability and BA didn't. So, I was offered the option to check partners. Sure enough, it came up with the AA flight.

Mileage for AA flight on AA.com - 20,000 AA miles + $2.50
Same flight booked on BA.com - 20,000 Avios + $152.50

So ... the situation hasn't changed from a couple of months ago, but did we ever figure out what BA does with the money it collects (YQ), ostensibly to be handed over to AA (but apparently isn't)? Should we look at it as a 'service charge'?