If I type /logoff, it cancels the countdown. I'm not turboing, not moving, not shooting, just drifting in space.

You can't logoff or warp in arcade mode.

I can warp in arcade mode.

you can warp in arcade mode because it doesn't abort if you accelerate.

However logging of requires you to not be accelerating at all but joysticks may cause you to accelerate slightly, therefore cancelling the logoff countdown sequence.

My joystick "twitches" so maybe that's why.