Thank you for your question and reaching out.
This behavior occurs because of a change in how the Windows Server DNS functionality manages the RDATA segment of an SRV record. In Windows Server 2012 R2 and earlier versions, the RDATA segment contains only lowercase letters. If a computer name contains uppercase letters, the DNS functionality converts them to lowercase. However, the Windows Server 2016 (or later version) DNS functionality accepts uppercase and lowercase letters.
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