Hi @Tom Ardern
You can refer to this: https://azure.microsoft.com/en-us/global-infrastructure/services/?products=functions.
Once you have selected any of the products along with the regions it will provide you the details on whether that region supports the product or not.
Update 11/30:
I had an internal discussion on this. According to our core team, premium is not supported for free trial subscriptions. For consumption, we block it because applications running on this plan need storage and storage doesn’t have a free tier. However, it is still possible to create a consumption app without storage but scale out will have limitations without storage i.e. it won’t be able to cross-stamp scale ( due to its dynamic nature ) and therefore will fail under load or will have unpredictable scaling depending on how over/underutilized it’s home stamp is. If the app is being created through script/arm template, this might work since the control plane is not blocking it but we are discussing this too to maintain consistency. If there is any further update I will update this thread accordingly.
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