IRROPS and expiring ticket
 

This is probably not-specific to UA, but does anyone know what happens in this case?

I'd an award booked at the grandfathered rates and was affected by the North America East Coast Blizzard. Fortunately I managed to find another award routing before my ticket expired (if I had stuck to the original routing on the next day I'd have to waitlist and didn't want to take the chance).

It would be a UA specific question. each airline is different. especially when miles are involved.

For instance on AS ticket validity period is 1 year from date of initial departure instead of ticketing date. So in theory one could book a ticket 330 days in advance and problem comes up on departure and ticket can be rebooked out another 365 days without any significant problem.

but whatever the rule is there is always a chance the ticket is expiring and you're in an IRROPS situation?