You will not need DMR as the future Sumner County simulcast system will be P25 trunking and P25 digital voice.
Two FCC licenses for three frequencies across ten sites was granted the end of last year. Showing as Public Safety Trunked simulcast system for 500 users with multiple
P25 digital voice emission types.
https://www.radioreference.com/apps/db/?fccCallsign=WRCR733
https://www.radioreference.com/apps/db/?fccCallsign=WRCP944
I would suspect they'll be pooling together other available UHF frequencies from existing licenses to add to the system.
Three frequencies (right now):
453.31250
453.36250 (same as Wilson County Intercity UHF channel, that will get interesting/annoying)
460.31250
Ten sites:
Bethel Rd New, Goodlettsville, TN
Center Point, Hendersonville, TN
Cumberland Hills Tower, Hendersonville, TN
Antenna Tower 641 Long Hollow Pike, Gallatin, TN
Music Mnt, Gallatin, TN
Mutton, Bethpage, TN
Oak Grove, Bethpage, TN
604 South Broadway, Portland, TN
Sugartree, Gallatin, TN
Westmoreland, Westmoreland, TN
Emission modes:
9K80F1D
P25 Phase II fixed-end 2-slot TDMA H-DQPSK data, per Harris MASTR-V literature
8K30F1W
P25 Phase I C4FM hybridized voice and data applications (most commonly seen on trunked licenses)
9K70F1D
P25 Linear Simulcast Modulation “WCQPSK” data (per Harris MASTR-V literature)
9K80F1E
P25 Phase II fixed-end 2-slot TDMA H-DQPSK voice (interpolation of MASTR-V literature)
9K70F1E
P25 Linear Simulcast Modulation “WCQPSK” voice (per Harris MASTR-V literature)
8K10F1W
P25 Phase II subscriber units (Harmonized Continuous Phase Modulation – H-CPM)
See the licenses/applications for further details.