I don’t think anything happens, assets other than the family home are assessed indefinitely. You will pay 7.5 % of the original land value for all years, regardless of how long that is.
Apart from the family home, farms and small businesses, with some conditions attached are recently being allowed to avail of the 3 year cap.
The HSE have the right to reassess at any time, but I am not aware of them ever doing so.
It is unlikely to be an issue, not many last 14 years, I think 3-4 is the average, one of my relations did last 9 years though.