I just want to make sure I am understanding correctly
If I book a ticket for $1000 (non-refundable) and the price drops to $800- can I cancel and rebook and get the $200 as a travel credit? If so, what is the expiration date on the travel credit? I think it is 1 year, but not sure if one year from the original booking or the date of the change? And is the expiration date when I need to book a ticket by or travel by?

thanks!