The apple vs orange thing about this discussion is we're not strictly talking about true radio propagation of P25 vs analog. We're talking about two DIFFERENT trunking systems, one being SmartNet and the other being SmartZone. The coverage area for the P25 system is larger than either of the two analog systems in question. The reason for this is the fact that SmartZone leverages all towers and doesn't restrict a radios ability to affiliate with ANY tower in the system even ones we are used to think about in a different "system". This is why the units suggested switching to digital. They're referring to a known "system" with a larger coverage area which extends outside of SBCo due to positioning of the sites in the mountains.
As an example: I can use analog in Fontana or Chino and not be able to talk to someone in Yucca Valley. However, if I "switch to digital", I can now do this. The reason isn't simply due to "switching to digital", it's just that the digital system is SmartZone vs the analog SmartNet.
I am told that the total number of towers in the valley alone is currently 6 on analog, yet when the system is fully completed, it will be 30. Where are they now in the process? I'd have to look at licensing via the FCC website. Rest assured that there are more sites today on digital.