add note about contacting support

Author: kenjenkins

content/docs/deploy/upgrading.mdx

@@ -287,6 +287,7 @@ Your Pomerium Enterprise version should always match the same **minor version nu
 
 To **upgrade** a Pomerium Enterprise deployment, we recommend that you:
 
+1. Reach out to your account manager to let us know you are planning an upgrade, especially if upgrading across multiple minor versions at once.
 1. First review the version-specific upgrade notes on this page for **both** Pomerium Core and Pomerium Enterprise for any changes that might pertain to your deployment. (If you're not sure, please don't hesitate to reach out and ask for clarification.)
 1. Take a database backup of the Pomerium Enterprise database.
 1. Upgrade Pomerium Core to the new version. For a replicated deployment, instances can be updated one at a time to avoid downtime.