Since I don't want Paul to tear himself away from working on the software for the BCD396T, I will answer this. (Also, I am the one that wrote the snippet you grabbed above.)
The Uniden BC296D, BC796D, and BCD396T (assuming you have uploaded the most recent firmware for the 296/796) all take the channel data from the data stream on Project 25, 9600 bps control channels including the tables for Base/Offset/Spacing(step) that are part of that stream. The Pro-96/2096 do the math to calculate the voice channels, but rely on the tables you enter as the
key to the problem. The
key is already contained in the data stream and Uniden took advantage of it.