Command /damage override type not working correctly

/damage with an override modifier seems like it overrides all barriers to damage such as resistance, armor, and whatnot. I noticed it also overrides the immunity after being hit however the damage is not actually being taken. An easy way to duplicate is to set a repeating command block with '/damage @e 1 override' and activate every tick. spawn a zombie and they will be 'hit' very fast but never die since every time they are hit in immunity, the timer resets making them invulnerable. Now if you set it to damage type none they will be hit much slower and eventually die. All I want is for override damage type to actually override the after hit immunity since it could help with some custom map special case scenarios.