I'd say that the build you recieved A-Grey was meant for the engineers to test the new features implemented. If all went well with that they'd then make it into a ezyfalsh II compatible bios and send it to you.
If this is indeed the case a proper beta bios will be released in a week or two like they did with bios 802 and then once we do their testing they'll release a final bios revision like 803.
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