Their response
Your ticket has received the following response:
Greetings, Thank you for contacting us regarding recent Hearthstone dust grants and missing cards. An update has been made recently to the forum post from our Community Manager regarding the full extent and resolution of these issues today, please see them at the post below: https://us.forums.blizzard.com/en/hearthstone/t/recent-dust-grants-and-missing-cards/79381 We apologize for the inconvenience and confusion this may have caused. Your ticket was identified to be about the issue addressed above. If the provided information resolves your issue, please mark it as Resolved. If this is not the case, please respond so a Game Master can manually review it.
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Regards,
Blizzard Support
Assume they mean this
1/20 Update:
The heal-up correction has been completed in the Americas region. That correction included running a script that subtracted the same amount of Dust that was previously added to each account, and also added back in the cards that were previously mistakenly deleted. Then, the refunds were processed as initially intended. The refunds only properly apply to a very small number of players, so the end result is that most players ended up with 0 extra Dust. We’ve seen your concerns, and we’ll continue to investigate your reports, but we’ve looked into it extensively and have not seen any player end up with less Dust than they started with (except for any Dust they spent in between the two adjustments).
The original refund script has been fixed, and is now being rolled out in each of the other regions. Because it was adjusted, most players won’t see any affects from it.
We apologize for the inconvenience and confusion this has caused.
No mention of players who crafted cards using un-earned dust…wtf