That is not a question we can answer from the forums perspective. You would need to talk with your Sales Ops/Account team on this. As this is a hard question to answer - based on the appliance, revision of AsyncOS you are running, and then take into account the extras you have added on and running --- IPAS, Sophos, VOF, etc.
Please open a dialog with your Sales Ops/Account team and/or re-seller.
Hope this helps!
-Robert
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