Light level is being scrapped. The vog gear, Crota gear will be Light: 0. It no longer exists. We level up via XP. Regardless of prestige level (you can check yours on Destiny Tracker if you were curious). Your guns will be obsolete and you will be at the same stage as all of those players that don't know what an oracle is. Grimoire score will be the new viewing point of experience. Best get grinding for grimoire and exotics.