I know this a late reply, but...
Yes. Here in the Houston metro area, 490 Mhz LTR systems are very prolific. As a former user of many of those systems, I personally used T/A a lot. It was almost standard programming for some shops. I did find the frequencies for what I was using at the time, and no, they weren't published/listed/licensed. I do believe some shops just picked random frequencies from what I could tell. Seeing as how we rented repeater air time, they were smart(marketing wise) to limit power output to the lowest levels the Kenwoods could do.