A little over a year ago, Zwift said they calculate your weight as the average of what you weighed when you set your 3, 5, 12, and 20 minute PRs. I assume this is still true, but that is just an assumption. However your weight is stable across all your PRs, so in your case I’m pretty sure they think you were about 70kg at the time of your PRs.
For each of those PRs, I divide the Watts by the W/kg numbers you provided, and take the average of those weights, then I use that value to divide your zFTP and zMAP numbers to see how it compares to the Category Enforcement boundaries (linked above in this thread).
