There have been some (many) people talking about the issues with sizing. If I recall correctly, sizes below xl were fairly true to size, but everything xl and up were all messed up. What I'm thinking is that they're going to do another run of the shirts, so they aren't repurchasing the out of stock sizes 'til they sell out of the others so they can do a whole run.

I like thin t-shirts, but mine was unwearable because of that size issue.