For the sake of some of the ornaments - I've bought every season pass but for the first two seasons I didnt complete them fully due to personal reasons. My idea is as follows.... Say I got to level 130 in the current battle pass - I would be able to use those extra 30 levels on say Season of the Undying to unlock the old rewards that I missed. I just think it would be nice, even if its only for the old armor ornaments.