Our 3 day Bahamas cruise in March was canceled and the 2 Cruise Next Lite deposits were re-credited. We subsequently booked a cruise in November with the 125% credit and 30% off next cruise and now are in the Haven for 7 nights on an Eastern Caribbean cruise. Only $3000 more than the prior cruise.
I called about the Cruise Next Lites which were going to expire Jan 2021 since we couldn't cruise again that soon. I was told NCL would extend them a year if I called the Cruise Next desk. As it turns out, I couldn't wait until November for a cruise and used them for a 3 day Bahamas cruise in July, 2020.
If you have Cruise Next deposits that may expire in the next year or so you should ask to extend the expiration date.