Automated WAC Patch Management is a PowerShell module to help you rebuild your Office Web Apps 2013 or Office Online Server 2016 farms in a (mostly) automated fashion. This PowerShell Module is a bit different from the previous Automated Remote SharePoint Patch Management script in that it is run locally on the Office Web Apps 2013 or Office Online Server 2016 servers. The PowerShell module is available on GitHub.
The patch handles multiple WAC/OOS servers, rebuilding the farm exactly as you had originally configured it after patching. If you have more than one server, a new server in that farm becomes the lead host. This allows you to have minimal downtime while you patch your WAC/OOS farm. Note that if EditingEnabled is set to true, you will be prompted to confirm the setting.