I can almost guarantee you it's not P25. Hearst is NOT going to pay for a P25 Radio, and my understanding is that P25 is not allowed on 450/455 mhz frequencies. It's Wide or Narrowband voice, and telemetry only.
There was some talk of petitioning the fcc to request digital voice on the 450/455 frequencies on those frequencies, but i believe the discussion was that stations were afraid that if they petitioned the FCC, they'd be forced to narrowband those frequencies.
I had heard this about a year ago, when I was working full time in broadcasting, so things may have changed since then...
My guess is that it's digital telemetry, but I'll take a look.
I started receiving this KCRA frequency in digital Saturday morning, and quickly dialed it up on a P25 capable scanner. It was not decoded and still displayed as "FM". It does sound like telemetry to me.
I wondered too if this was related to the Amgen Tour. I guess we'll find out soon enough once the tour is over if the channel reverts back to analog. I actually get a lot of value listening to this channel and metro air to air.