Thanks for this great thread! I just want to confirm that I have done the right thing to extend my certificate:

I have a companion certificate expiring in less than 2 hours, so have been reading this thread for the past half hour to figure out how to extend or save it. Since everything is refundable within 24 hours, I figured that I might as well try to use it, post here, and cancel it tomorrow (worst case). We might be going to Maui sometime in the fall, but are not sure of our travel dates yet. So I booked full coach fare SJC-OGG for $1400+. According to this thread, I can now firm up my dates and change the dates/times/destination (if we want to go to SFO-MCO in Spring 2021, instead, for example), and keep the companion fare intact? I have never purchased a refundable fare before, so have never tried to change a ticket. However, I am MVPG for this year (and last), so I have made changes and received wallet credit before. It sounds like I should be able to make changes online or by calling, and any extra funds will be refunded to my credit card? And the worst case is, we don't go on either of these trips and I get a full refund and all I've lost is the companion certificate?

By the way, my next companion certificate showed up recently with an expiration date of 1/19/2021. Ideally, we may use that one (and this hopefully extended one) for our family of four to go to MCO.

Thanks for any advice and let me know if I am doing this correctly.