Thank you for reaching out.
I understand you wish to know that the public IP address associated with the Azure Firewall in your secured VWAN hub is a static IP address.
Yes, the IP address associated with the Azure Firewall is static IP address.
In Azure public IP address can be created in two different SKU Standard and Basic. More details on IP address SKU here
Standard SKU IP address is a static Public IP.
As documented here Azure Firewall supports Standard SKU public IP addresses. Basic SKU public IP address and public IP prefixes aren't supported.
Hope this helps! Please let me know if you have any additional questions. Thank you!
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