Latest update dealt with the issue of beargear always spawning on the first day of autumn, now he always spawns during last few autumn days with random and confusing night warnings a couple of days prior to that. Here's what's happening:
OnSeasonTick (beargerspawner.lua(127)) relies on seasontick event to be notified about seasons change and on the first day of autumn it schedules to spawn bearger in 3.75-6.25 days as expected. But latest update also changed how often seasontick event is raised, intentionally or not. It is now raised daily, instead of only on season changes. Because of that on the second day and every following autumn day spawn gets rescheduled with shrinking delay, due to the fact that delay depends on number of remaining days, until at one of the last days delay becomes smaller that a day's duration and the poor creature can be free at last.
Wait/skip until the second autumn, bearger spawning gets delayed until the last few days.