@Mark Robson
Azure Files currently offers four different tiers of storage, premium, transaction optimized, hot, and cool. You can see the information about storage tiers located here. Pricing can be found here. It is possible to change the tier for your GPv2 storage account, but there is not currently a built in way to have the data moved from a hot to a cool tier storage account automatically.
For product feedback and feature requests I will refer you to our feedback forum. This allows the community to add their voice and upvote popular ideas. The forums are monitored and responded to by our product teams.
https://feedback.azure.com/forums/217298-storage
Hope this helps. Let me know if you had further questions or need further assistance.
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