Is it possible to use my BA miles for an Aer Lingus flight? I am looking to fly BOS-DUB and Aer Lingus has a good flight for this, but I have a feeling I would be required to use BA since they serve these airports. Maybe I'm wrong.

If I can use my miles this way, how would I be able to check the availability of award flights on Aer Lingus?

Thanks in advance!