I used a credit in May that was expiring in June to
book a trip in September. If I cancel the ticket do I lose the credit since it would have expired or is the validity extended?

If I am understanding the Alaska website correctly I would have 30 days to rebook travel up to a year in the future. Is that correct? Thanks!

Your credit certificate will remain valid for 12 months from the issue date of your original ticket, or 30 days from the date of exchange/cancellation (whichever is greater).

https://www.alaskaair.com/content/mi...0charge%20card.