SEVERAL... like back when i was working there, so early 2000's... years ago, the plan was to switch the dispatch frequency.
154.13 is one of the statewide mutual aid frequencies, and like the rest of those frequencies (155.5, 154.31, etc) any agencies still using them were requested to switch off so that they can be common statewide.
With the anticipated buildup of the 700mhz TRS, the statewide MA channels were supposed to get a simulcast 700mz frequency.
This was supposed to happen by 2014... yeah, it didnt.
Primary reason that it didnt happen was lack of infrastructure for the 700. Secondary reason was several larger counties, Dona Ana being the top of the list, did not want to immediately switch, primarily due to financial issues. Keep in mind that fire dispatch used to use minitor 2 and 3's. Re-crystalizing several hundred pagers, reprogramming several hundred radios that were only single channel or dual channel, having mutual aid agencies re-program, etc.
With the new facility for MVRDA and the fact that everyone now has programmable radios and pagers, the swap was significantly easier.
They just swapped one of the tacs in as dispatch, relabeled the .13 frequency as state fire 2 or state fire tac in their radios, and it was done pretty much in a weekend.
Also. I hear they may change the way tac's are assigned.
For a while, with the exception of North tac, which was only used in the Rincon and I25N corridor (due to interference from a repeater in Juarez) the tacs were haphazardly assigned per incident by the IC.
Now they're supposed to assign state fire (154.31) as the primary tac for any actual fire (largely because it is patched to one of the digital talkgroups in the city) and assign the remainder of the tacs geographically to any other incident or training event that needs them.
I recall the idea down road was to have several southern counties have dual band capable equipment once 700 started taking shape. While a select few have a few running around not many yet have them nor will anytime soon. It will be some time. The state is planning on smaller entities to join a 700 trs down road to help with costs and where pheasable for 700 while some keeping vhf. Many rural and smaller entities will not be able to afford the trs Costs for joining however this can be solved in work arounds. A couple I know of have said when time comes they would look at conventional 7/800 use and have the trs when it comes in the equipment for interop purposes but want to stay conventional. With monies being a issue all over I don't see drastic changes anytime within the year or two overall but process will continue slowly.