This is my take on this.
The RCMP have been given a mandate to ban anything AR-15 ish by the Turd Reich, so they are doing what is necessary to follow this directive (rewritten FRTs etc).
The problem for the RCMP is that these firearms were given an FRT that distinctly states they are not AR-15s before all this craziness came down the pipe. To the uniformed observer however they appear similar so must be included to please the Turd Reich. The RCMP most likely know this will result in legal challenges but thats not their problem, they have fulfilled their duties.
Please note I am not defending this - quite the contrary - I think it draws attention to how ludicrous it all is but the RCMP don't care as they can check off the necessary boxes.