I was lucky enough to hit light level 320 this week after golgo challenge.I sacrifice my 320 titan helmet and 320 chest for that =( I thought we might be able to stand a chance decrypt exotics at 320 when our character reached 320 light level.However sadly no,all decrypted engrams were at 310. Skip the video to 5.11 if you're interested in watching.The beginning few minutes were just sorting out my stuff. I decrypt: -9 special engrams -4 gaunlet engrams -8 helmet engrams *Edit.1* :-exotic still decrypt at 310 even though i got the exotic drops at 320 light level.