Just a bit of additional information on this. The Houston Fire Department switched off the UHF Analog at about 2:00 AM local and are now operating strictly on the TxWARN P25
layer 3 channels only. In other words, all TDMA. So far no one has found any FDMA simulcast of the HFD channels. It is unclear at this time if the UHF system will go back on the air at all as it had a failure sometime last night dictating an early change.