Randomly switching between G20 & G21 mode

Hi...I am currently running 2.7.11 and use gmocappy as my screen. I run inches so I have G20 set, but sometimes randomly it will switch to a G21. What could be causing this? My ini files only reference G20, as far as I know G21 is not referenced anywhere in my configs.
Its more of an annoyance then anything else at this point, but would like to get it fixed as restarting Linuxcnc everything it happens to get my G20 back gets old.

You could just MDI a G20 instruction, no need to restart.

I would suspect that the G21 instruction is in a remap or subroutine file somewhere.
As a first step I would grep the config directory for "G21"

Thanks Andy never thought of doing that.