Leaving aside that the vast majority of people on such lists are nothing of the sort, your presence on them is evaluated if not every time you book a flight, but every time you check in for one.

Otherwise that's a pretty gaping loophole. "Get Precheck and then go to terrorist training camp, you're safe for a few years".

(All of this is notwithstanding the fact that all of this is absolute garbage security theater, and I say that as someone with Pre and Clear.