As you create new versions of your templates, you will eventually want to upgrade your existing tenants.
You can do this on the Multi-tenant tab for the template.
Upgrade Multiple Tenants
Navigate to the template site detail screen
Click on the Multi-tenant tab
Scroll down to the UPGRADE TENANTS section
For the Upgrade Tenants To This Version field, select the version that tenants will be upgraded to
To upgrade all tenants, click the UPGRADE ALL TENANTS button
To upgrade a subset of tenants, select one of the other options and click the related UPGRADE button.
Upgrade A Single Tenant
To upgrade a single tenant:
Navigate to the tenant site detail screen
Click on the Multi-tenant tab
In the UPGRADE OR DOWNGRADE section, enter the new version you will be upgrading the tenant to (the default version will be the current version the tenant is running)