with apologies.....
as i understand the plan, the ksp 800 meg system is to augment their own 400 meg system primarily as tac comms for special units (drug interdiction, etc--hence the air interface) and to allow wider use of mobile data terminals.... from what i understand the system will be both analog and digital wiuth some talk-groups encrypted for security purposes...
i have been told that, in some counties, various non-ksp agencies will also be on the system to allow broader coverage thanis currently available on extant systems....
the 400 meg system will remain in service and the 800 meg system will develop slowly over a number of years as money--federal and state--becomes available.....