The town of Derry, Maine began as a beaver trapping camp in the 18th century and the settlers awoke It, who had crashed there on an asteroid thousands of years prior.
He was referencing the history of It and of Derry itself.
While there may not be any firm plans at the moment, and the folks at Warner Bros would presumably want to get Stephen King’s blessing first, Gary Dauberman did mention the story of the beaver trapping camp when the spinoff possibility was raised to him.