Thanks guys, that makes sense. I've been monitoring on and off for years, but it's hard to keep up. I finally have my SDR system working pretty decent and was just something i've noticed. I am only within earshot of the Monroe County simulcast system.
I long ago downloaded the information from the database into my sdrtrunk installation, but I've since let my subscription lapse - so i'm going through and updating unknown talkgroups. Essentially, I have sdrtrunk set up to monitor all calls (including unknowns) excluding encrypted or data calls.
I figured out the hard way that I'm limited to a backlog of about 6 million calls LOL (using the hardware I have)