I just installed this and it seemed to work. Players that already had played more than the set amount of time, weren't base protected anymore. But now i noticed that one of those players that played alot don't get the "Not protected" message when checking but this:
This entity cannot be destroyed because it was built by a new player (-1h -39m -49s)
Here's proof:

This entity cannot be destroyed because it was built by a new player (-1h -39m -49s)
Here's proof:
