According to my progress tracker in Hearthstone, under Achievements - Collection - Classic, I am missing 4 Classic cards. All legendaries.
However, I have every single Classic card in my collection. The difference is, maybe, that I have 3 of them in Golden and not as normal Legendaries.
I actually got my final Classic card, a Millhouse Manastorm, from the Golden Classic pack reward after the patch hit.
My theory is that it doesn’t count the Golden cards. That leaves just one additional anomaly, because my progress is missing 4 cards and I have only 3 Golden Classic legendaries.
Perhaps it has to do with the Golden King Krush I received for having 500 wins as Hunter? I don’t know. I just know that I didn’t get the rewards for achieving the full collection of Classic cards (not the new format; the ‘normal’ old Classic cards).
Anyone else seen this?