We've all been there ... you think you have a distant one, and it turns out to be a new local.
And visa versa.
I'm a big advocate of PL / DPL tone monitoring for conventional channels, and all my base equipment can decode or decode-and-filter tones. Last spring, I was making changes to a Pro 2006 scanner file, so that scanner was running in carrier squelch mode.
Just after 6 p.m., the 2006 stopped on 39.10 - which the county fire departments in my neighboring county use for dispatching. I recognized the callsign and pager test broadcast, although it wasn't my neighboring county ... it was the municipal dispatcher testing the rescue squad pagers for the N.J. town I grew up during the 60's (Scotch Plains, in Union County).
So, you never know.