Does every MacOS update (even minor releases) overwrite auto_master?

I cannot be sure, but it even minor updates seem to overwrite auto_master and screw up my nfs mounts.

Just the other day my Mac updated on its own (I don't know why, perhaps I allowed it accidentally when I tried installing a new wacom driver). But regardless of why, my computer updated to 10.15.7 (from 10.15.6) and suddenly my auto_master file has been reset to factory defaults and none of my nfs mounts work anymore.

Can anyone:

a) verify that auto_master gets blown away by updates

b) figure out a way that I can preserve my system settings so that I don't lose access to my network on updates

and

c) let me know if I should not be modifying auto_master but instead use some other mechanism for mounting nfs shares at startup

It is not an extreme hardship, but since I am not a networking expert, I have to relearn how to mount my nfs shares each time this happens (I have sent myself an email about it this time in the hopes that I will remember to look there for instructions).