Originally Posted by
cova
If also could be that Aer Lingus won't let AA passengers in..
That is not the reason. The BA lounge has long refused to let in passengers flying on AA tickets that should have access as OWE. Sometimes they allow people in; sometimes not. YMMV. But it has nothing to do with Aer Lingus. This issue predates IAG’s purchase of Aer Lingus.