I'm AA Sapphire and need someone with experience to help prevent me from looking like a fool at LHR T3.
OneWorld lounge rules state:

The following exceptions apply:

American Airlines and Qantas offer programmes enabling customers to pay to gain access to their lounges. These programmes are not part of the oneworld agreement, and members of these programmes are not entitled to access lounges under the oneworld agreement.

So, this means if I'm flying in coach through LHR as an OW sapphire, I have free access to Admirals, whilst a business class ticket on BA connecting to AA would give me access to Admirals and Galleries but not the CX lounge in T3.

Is this correct? Thanks all.