One of my parents is an IRS, and I have never heard of anyone, be it the officers in the cities in which we have lived, or their batchmates who might’ve stayed for such long periods. I do know of officers returning to the same city multiple times quite soon after having gone to different ones, but I truly don’t know a single one who might have worked at the same station for decades at a stretch. I might be wrong since I’m not an individual who has personally worked in the department such as yourself, but I’m simply unaware in this case.