Based on the information you've provided, it appears that your Azure account may be benefiting from initial credits typically associated with an Azure free account. However, the absence of the "Free Trial" label in the portal and the presence of an "Upgrade" option suggests that you may not be on a traditional free trial.
Generally, an Azure free account includes:
$200 in Azure credits valid for the first 30 days.
A limited selection of free services available for 12 months.
The ability to upgrade to a pay-as-you-go subscription at any time.
If you're seeing the option to upgrade, it likely means your account is in a state where it's eligible to transition to a pay-as-you-go model once the credits are consumed or the 30-day trial period ends.
To confirm the exact details and status of your subscription, we recommend checking the "Subscriptions" blade in the Azure portal.
https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/upgrade-azure-subscription
https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/avoid-charges-free-account
Kindly let us know if the above helps or you need further assistance on this issue.
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