Originally Posted by
CDKing
WN is date of ticketing
Interesting. To make sure I understand it correctly, I'll use an example.
Suppose on 1/1/2014, I booked a AS and another WN ticket, both for travel 11/1/2014-11/30/2014. I decide to cancel the ticket today (5/13/2014).
For the AS ticket, I have to use the credit towards another trip that needs to be completed (or started

) by 11/1/2015. I can change whenever I like, however many times I like before 11/1/2015.
For the WN ticket, my last reticketing must be completed by 1/1/2015 (for travel up to EOS). If I choose to cancel/change ticket after 1/1/2015, original credit from the PNR booked on 1/1/2014 will be lost.