I happened to be sitting at the computer today and saw a couple of transmissions on TG 35731, "US Probation & Parole Agents". Looking back at all of 2020, I heard this talkgroup on one day each in January, February, March, and May, and not at all in April and June. So having it live for four days in a row is interesting. I'm pretty sure they're coming through the main KCMO site.
I caught a few transmissions "live"; some users are clear and some are encrypted. I don't have recordings of past transmissions, so I don't know what the general case is.
Looking at the logs for July, this group first lit up late on 2020-07-20, and has been active every day since then. It is active at various times of day; I've seen it come up, talk for several hours, and shut down for the day, and I've also seen it come up, talk for a couple of hours, shut down for a couple of hours, and then start talking again.
Looking at just July, there have been a few KCMO PD radio IDs talk on it (4001xxx, 4104xxx, 4105xxx, 4117xxx), and one KCMO Fire ID (4007xxx). Most of the traffic, though, comes from 4054xxx and 4055xxx IDs, with a few more from 4497xxx IDs.
I don't actually know which agency uses the 4054xxx IDs. I have heard a few transmissions from that range in the past, which I have identified as officers of some kind, but I'm not sure what agency - based on the context or talkgroup I heard them on, I have tentative notes of KCPD, VA, or just "United States", but I'm not sure. I have no notes at all on any of the 4497xxx IDs.
The 4055xxx IDs I usually hear are definitely from the VA Hospital, usually hospital operations. I've heard a couple of officer-type transmissions from those IDs in the past, as well.