Comment by simosx

You can hold off the update of a snap package for up to two months by enabling the appropriate key at https://snapcraft.io/docs/keeping-snaps-up-to-date

I suppose the rational is that updates should happen. You can take your time to hold updates for up to sixty days but they should happen anyway.

The certbot snap package is published by the EFF/LetsEncrypt themselves.

You could also trick snapd that you are on a metered Internet connection, therefore avoid updates.