Originally Posted by
poohfighter
Originally I had booked it for exactly one year out from my ticketing date; however, I received word of an itinerary change from Thai, so I called United and had it rebooked for a few days later
How did you book it one year out from your ticketing date? UA only allows ticketing about 330-335 days in advance.
Tickets are good for one year from the date that they're issued. That expiration date should be on your receipt. You should probably double-check, as UA is likely to be somewhat less flexible if what you've described is accurate.
Originally Posted by
poohfighter
Also my original flight isn't available any longer.
UA will not be able to reinstate a ticket if there's no availability left to put you into. You should look for alternate dates / routings / etc.
You're likely to get one more change, at most (that's on the assumption that you can find a sympathetic supervisor and your ticket isn't actually past expiration).
Good luck...