I had an AA-sold ticket to TLV last December. On the outbound, I had an LHR-TLV on BA that was not an AA flight number.
Connection blown by a MX issue that delayed our LHR arrival. AA rebooked me on LY.
Never got credit in my AAdvantage account. Called AA and they basically said what's being discussed here... that they had to credit it on distance, but they could not give me EQD for that LHR-TLV portion.
So the system has some kinks, still, that need to be ironed out.