*A has quite a few standards and working groups. Their first aim is to provide a seamless travel experience, so checkin and lounge etc is covered, and during irreg *A partners can rebook onto each other without having to double check and get endorsements. So in the above AI case the ground staff could have rebooked the entire flight onto alternative *A flights.

They also have working groups that come together to discuss policy and prepare plan on how to help each other should one partner have incidents (crashes, 9/11 type situations etc).