It's true that class D amps can run with nothing connected to it, but that isn't "no load". That's an infinite load. "No load" is a short, which will destroy a class D amp pretty quickly (ask me how I know ). I'd be concerned that depending on the the jack and the plug, there could be a chance that the tip and sleeve of the jack could short out on the ground ring of the jack while unplugging especially if it is pulled out with any torque on the plug . Is it likely to happen in the short time of unplugging? I don't know, but I wouldn't chance it myself.
I've never opened up my KPA, but forum members mentioned that it uses an IcePower amp. When I blew my other IcePower amp, I contacted IcePower and was told that the amp was un-repairable, and basically trash.
However, it you replace the 1/4" jacks on your cabinets with Speak-ons, you would be perfectly safe.