Thanks guys. I called BA first thinking that they did the booking so should sort it out. However, they were less than helpful, just repeating what MMB said and telling me I needed to call American.

Using the AA record locator that shows all 4 flights, I'm unable to change the seats for the LHR-CLT leg as it says it's a BA flight. The agent at American "offered" to do it for £30pp.

I'm stuck between BA and AA neither of whom are being especially helpful. Maybe i need to call BA and insist they sort it out..

Al
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