Set stats promotional email is likely displaying the incorrect mastery level for each set.
For every set going back to Final Fantasy, my mastery level has been displayed as 65 in the generated stats email/image, in the promotional email that has the most-crafted cards for the set. Given that the 5 sets in that time have had varying lengths of times, I find it unlikely that I actually hit that number exactly in every set. Additionally, another player who posts their stats in a group chat has also had their level remain the same going back to Aetherdrift. I've attached my stats images for reference, all pulled today, though I checked my group chat and I see identical numbers.
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Newershadow#62599
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