Hi @Mark Dale
Thank you for reaching out to the Microsoft Q&A platform.
No, Azure Pack is not eligible for free ESU updates. The free ESU updates are only available for Azure Stack customers. If you have Server 2012 R2 instances running in a Hyper-V environment based upon Azure Pack, you will need to purchase Extended Security Updates (ESUs) to keep them running past the end of support date. You can purchase ESUs through the Azure portal or through your Microsoft account representative.
Please note that the cost of ESUs increases each year, so it is recommended to upgrade to a newer version of Windows Server as soon as possible.
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