Replying to Flylow pattern change?

Was at Sports Basement yesterday hunting for sales and tried on a bunch of new Flylow pants/bibs. The mediums were laughably small - couldn't even get them past my thighs. The larges were fine in the waist but too tight when I'd try to bend my knees. The XLs were okay from a movement perspective but I'd def need a belt for the waist. I'm not steezy enough for XXLs so didn't waste time trying them on.

Then I happened to look back in the consignment section and found a pair of Flylow ski pants from 2016 that looked good - tried them on and the fit was perfect! The waist was 33" on the money, the fit was loose/slightly baggy, and articulation was excellent when bending my knees/squatting. The size? Medium.

So what's going on here? It's crazy that a company would change their pattern that significantly, but it seems like Flylow has either switched suppliers or patterns. Does anyone know if this is common, and what would drive a brand to switch up their sizing so dramatically?