I've never heard this before, but hearing it now, UPR583 on DPS Dallas, running 28 checks and the works. Guess someone might add TXDPS to Rail Police Channel line-up. Pretty cool catch - I've never heard it before.
In San Antonio I have heard them all over the place from DPS to all the Rail channels to Border Patrol Channels. Think they can pretty much get on any channels for there area
I remember mentioning this about 2 years ago, coming through San Antonio DPS. I thought it was strange also. I've also heard them on CBP/OBP repeaters. One of my PD buddies' father worked in the UPRRPD, and went all over the states. I never thought to ask him about it.