Originally Posted by 84fiero

Details can help with nuances in particular circumstances/airlines that may affect your decision. The airline isn't going to find you out and hunt you down based on a Flyertalk posting!

Just because a partner carrier is operating the last leg doesn't necessarily preclude a rerouting due to IRROPS. It's possible a cancelation on the "B to A' return segment could result in you rerouted via that same partner - or even a different partner airline - instead, and not touching "A" at all. It's probably not a huge chance in most cases may still be possible. Knowing what airlines and routes involved might provide a better guesstimate of the risk of that occurring.