Undestr/No decay occasionally failing randomly

I have several zones protecting certain builds with the Undestr and NoDecay flags on. 2 times this wipe i have logged in to see my building half decayed. Both were after 12 or so hours of uptime.

Flags turned on

I have had experiences with this mod where after the server ran for a while, the mod would stop functioning completely. I could try to reload it and get an nre.  If I re-download the plugin and overwrite the existing plugin,  it would then start working fine. Very odd.