The IROPS repair tool works OK when changing from a one-stop routing another one-stop routing. But it chokes when you want to change from a one-stop to a 2 stop routing (sometimes that's all that is available.)

Another issue with the IROPs recovery system is that is searches for new flights within the next three days - of the current day, not of the cancelled/delayed flight. On Sunday I had a flight cancelled for Tuesday morning; the only alternative dates I could search were Sunday, Monday, and Tuesday. Given the winter weather and the waiver, I need to start searching from Tuesday onwards.