will this apply to licensed armed private investigators too?
That is governed by CLEET regs and I haven't read of any law changes affecting that part of their regs. It will remain a gray area as it always has been, at least since the inception of the SDA. CLEET regs say armed PIs and SGs can only carry while "on duty" (and not going to/from) but that rule has been observed in the breach for quite a while. Most PIs of my acquaintance have an OK SDA card so as to be covered at all times as regards the laws and regs of CLEET and OSBI. CLEET has an annual meeting of their authorized instructors and schools so that will likely be when they update those folks so it gets passed on to the field with new classes.