Non refundable deposit

I understand if you cancel before final payment date that you get the deposit as a future cruise credit (less $100pp) to use within a year.
Is that a year from date of cancellation or a year from original sailing date?

I was told that it had to be used within 1 year of the issue date.

This is the wording:

Nonrefundable fares – If you have booked a nonrefundable fare a $100.00 per person change fee will be applied for any ship or sailing date changes. Cancelations will incur a $100.00 per person cancelation fee with the remainder of the deposit applied as a Future Cruise Credit to be used within 1 year of cancelation.

I find that odd. If i would like to change sailing date from aug 2019 to july 2020, it wouldn’t be possible? If i were to change the aug 2019 sailing today, i would have until nov2019 to sail? Then I should just wait with changing until just before final payment date ‍ so i would have until April 2020 to sail.

It would be more logical if the FCC was valid for a year from original sailing date