Trek changed all the national champions jerseys pretty quickly. Most notably Zoidl and Kiserlovski, Zoidl just had the one sleeve and Kiserlovski had those red squares on both sleeves, he looked like a fackin clown. I would say now they all have decent ones, except Roulston, but his is also at least distinguishable now. Devolder and Jungels had OK ones to begin with, but they also changed a bit.
I wonder if that is maybe a PR strategy? I don't think it is a terrible idea to slightly change these national champion's jerseys throughout the season, makes for a little added fun. As long as they remain easily distinguishable, of course. Also don't know how UCI rules apply on this one (cf. Milram and Livestrong debaccles)