Depending on the make/model it could be an image from the lower VHF or even UHF
Hell even 800/900 as I had one scanner that would pick up 900 TRS in the 173 Band
i haven't had a image spread quite that far before, but certainly close. i have found for some reason the 160's and 170's seem to be areas prone for issues for me.
There have been unid P25 transmissions from Central NC with $210
maybe that agency went Analog ?
hence why i saw this and said "oohhhh reaaallllyyy"
The other option is use a different make/model radio to rule out, that it might not be an image... I've used my Yaesu to do this in the past for RX
i have come to a point where i almost always use two different manufacturers at the same time, if possible, before i consider something confirmed to my satisfaction.
i have a pro-668 that has many good points, but will allow nearly anything through and indicate that "387.4500 PL 67.0? Talking about taking trash to a dumpster? oh yeah man don't worry thats correct. i am a pro-668. i know whats up" turn on a uniden and it says "he's lying. like always. lying man. he'll spew anything out. not me"
the thing that makes me lean most towards it being an image or something along those lines is A: use of DPL/DCS and B: routine nature of traffic
I just really dont see much DPL in use in general, but even then mainly UHF business. only one federal user have i run into using DPL that wasn't Ranger/Forestry/Natural resources related and they have since gone DMR.
the fact that its gone silent though, kills off my image thoughts and makes me think you may have had a "good reception period" as i call them which occur from time to time for me. Shaw AFB trunked system in the 160's i receive periodically from central nc, as well as some Fort jackson in SC that is in the 380's. i never, ever recieve anything further out than that, distance wise, in any direction, but get it frequently enough that it seems that is just outside of the fringe area receivable if one is trying really hard.
so i would think, figure out how far out is the most distant thing you recieve on a regular basis, with low to medium effort and then add 30% +/- distance-wise, and start checking to see whats reported that might match.
or not
but if you catch a $210, holla