So I am back again to molest the more experienced in here. At my first departure airport they still could not give me BA boarding passes. Now I am sitting in the AA lounge in ORD and they could not either. However, now I could use the BA App to check in for the remaining two flights. Seems like from now on BA controls the booking again. However, my question is, should I worry about my bag? It is tagged thru, but will the system know that it is with me?