In the post from Bungie last week it stated that All Exotic armors earned since The Edge of Fate launched will be automatically upgraded to have Tier 5 stats. Now is a good time to farm all of your exotics. Farm Xur, engrams, and if you still have them, your exotic armor requisitions (we were given 20) from Ada. Since they are all being upgraded to T5, even a low 58 stat is valuable if the stats are in the right spots. If you still use some pre EoF Artifice exotic, try to reaquire them with the perks you want on new exotics. All the old pre EoF armor will be weaker and low stat after this update goes live.