UPDATE 10/17: Customer was able to solve the issue by using a different subscription. They mentioned -
"I was doing the test on my Visual Studio subscription, and it was not working there with the errors I mentioned. But I tried to deploy on an existing company subscription, with existing Classic Cloud Services and I could deploy without issues and even tested the AutoMigrate."
10/11
Yes, customers can update existing classic cloud services as they did before. However, the subscription needs to be whitelisted for creating a Classic Cloud service depending on the type of subscription.
I will need your Subscription details for the same. Please provide the details requested via private comment.
Reference document regarding Azure Classic cloud service updates : https://learn.microsoft.com/en-us/azure/cloud-services/cloud-services-update-azure-service
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