Originally Posted by narvik

Brace for impact! I can not imagine any scenario where United IT would get such a feature automated in a way that would work well.
Considering how they butchered the meal pre-ordering, I would envisage it going more like this, than your utopian example:

"Sorry narvik, your flight from HND to EWR is canceled. Would you like me to suggest an alternative flight for you?"
"Yes"
"Sorry, I didn't quite get that. Would you like me to suggest an alternative flight for you?"
"Yes"
"Sorry, I didn't quite get that. Lets try this a different way. For alternative flights, please press 1, to hang up, press 0"
"1"
"It looks like there are no other flight to EWR available today. There is an upcoming flight to a nearby airport available. Would you like me to suggest nearby airports?"
"Yes"
"Great news. There is a flight to San Francisco (SFO) available at 3:15 pm. That is only 2'560 miles away from Newark (EWR). Would you like me to re-book you on this flight instead?"
"No"...under breath: "that flight already boarded and is closed...it's 4:45pm in Tokyo now"!
"You are confirmed on flight xxxx to SFO. Your seat is 35B. Boarding begins at 2:25 pm at gate C145."
"Confirmed how? Which day is this for?"
"Sorry, I don't understand your question. Thank you for being a loyal 1K member, we appreciated your business. Goodbye."