There is a new VARA object for Automic Workload Automation version 21 - UC_SERVER_TLS_SETTINGS that allows for the use of defining a custom action to be triggered if a custom action is close to expiring, but "close to expiring" does not have a defined time.
Release : 21
Component : AUTOMATION ENGINE
The time for the expiring certificate begins at 30 days.
This information will be updated in the documentation.