Hilton Honors introduced rollover nights in 2018 (read more here) that allows members to roll over the nights stayed in any calendar year in excess of the status reached to the following.
Rollover nights don’t roll over from year after year. Only the nights consumed in 2019 over the status were rolled over to 2020.
Here’s what shows in my online page:
The website correctly shows 10 nights stayed for 2020.
The app is still updating the status for 2020:
The rollover for my account has been processed correctly. I consumed 70 nights with Hilton in 2019 and had 14 or so nights rolled over from 2018 (that I didn’t need).
As long as you reach your Diamond status with nights yearly, there is no benefit from these rollovers. They could, however, help Silver and Gold members easier to reach higher tier and those Diamond members whose number of nights consumed varies yearly.