In addition to the upgrades to the Customs and Border Protection (CBP) radio network in Florida, it appears that the Federal Protective Service (FPS) has also upgraded to P25 digital.
410.8 MHz, N201 is now being used by the FPS in the Miami area. The same frequency is most likely used through out this FPS region. Some sites may have different NAC's.
You can read more about the CBP upgrades and frequency changes in the latest edition of The Spectrum Monitor, http://www.thespectrummonitor.com/index.aspx