Used to get that a lot with my 690, but could work around it by changing how I shifted. Normally you flick the shifter with your toe, then release clutch, maybe get false neutral.
But if you hold pressure on the shifter with your toe until after you release the clutch, no problem. Apparently, that’s the way you should do it anyway, but admittedly I’ve got out of the habit now with the dirt bike.
But might not be relevant on the track anyway. Are you even using the clutch to shift?