Is it possible to reset a single !M metadata value?

[cprima]

Let's say I did set "permanent across reboots" !MEXPX=150,
but after a few days would like to un-set this value.

Would I need to set !MEXPX=30,
or is there a reset method?

I know that !RESET will reset all metadata values and this is certainly a possibility for me,
but maybe I just missed an alternative.

The usecase is:
I want to quickly change with a QR code

• from in-camera stabilized
• to stabilization in post

That requires me (un)setting

• EXPX
• EXPN
• lens
• Hypersmooth
• and potentially some more

[dnewman-gpsw]

!MEXPX=0 or any !Mabcd=0 disables the function.