Hi Ranjith Velamala,
Welcome to the Microsoft Q&A Platform. Thank you for posting your query here.
When performing an in-place upgrade on Azure Windows VMs, the VM properties on the Azure portal aren't updated; the changes are only reflected within the OS. This means that the source image information in the VM properties, including the publisher, offer, and plan, remains unchanged. The image used to deploy the VM remains the same, and only the OS is upgraded.
Please refer the below document for your reference: In-place upgrade for VMs running Windows Server in Azure
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