As far as I can see, AA.com does not sell this connection and ITA matrix will also not allow it either. That does not look like a legal connection. Did AA or BA sell that to you or did a TA put it together?

If the former, you should be OK: if they agreed to sell it to you, then I would expect them to take responsibility in case of misconnect.

If the latter, I would be somewhat concerned that AA and BA might refuse to rebook in case of misconnect on the ground that it was below MCT and, as such, AYOR.