This does affect existing GMRS users. The FCC left a 12.5 KHz guard band at the lower and upper edges of the GMRS band for good reason. Receivers of existing 25 KHz bandwidth GMRS subscribers and repeaters will be affected by transmissions on those proposed channel centers. I urge GMRS'ers to take a position on this issue or two GMRS repeater channels will be demolished in major urban areas. If you are of the opinion that 12.5 KHz narrowbanding is a good and useful mode for GMRS, you should take note that there is a serious performance impact with 12,5 KHz NB, one that can not be resolved by going digital as many Part 90 licensees find themselves doing. Part 95 cannot use digital mode. Further there is the interference from the proposed rulemaking. If the FCC allows this, be prepared to endure MotoTrbo or NXDN digital interference within your repeater (and subscriber) receiver bandwidth.