I talked to the admin assistant for a PD in central Indiana today, they switched their phones to firstnet and have been disappointed with the coverage. Part of it was due to the large crowd at the 500, AT+T and Verizon put up temp sites and small cells but officers' personal Verizon phones did not have the problems AT+T did.
Another article had this from an Illinois PSAP admin.
'AT&T’s poor service in 9-1-1 and public-
safety-dependent leased lines in our
footprint is an overarching concern.
And I will not be shy about calling out
Verizon if it under performs. '