Merge pull request #247891 from axelgMS/axelgMS-patch-1

Update node-image-upgrade.md

Author: prmerger-automator[bot]

articles/aks/node-image-upgrade.md

@@ -14,6 +14,8 @@ This article shows you how to upgrade AKS cluster node images and how to update
 
 > [!NOTE]
 > The AKS cluster must use virtual machine scale sets for the nodes.
+> 
+> It's not possible to downgrade a node image version (for example *AKSUbuntu-2204 to AKSUbuntu-1804*, or *AKSUbuntu-2204-202308.01.0 to AKSUbuntu-2204-202307.27.0*).
 
 ## Check for available node image upgrades