I'm a new player and have only had time to buy and play forsaken so far, I'm really interested in Eriana's vow through the exotic cipher but it says I need Shadowkeep. I first intended to buy it maybe as a package with beyond light. Does anyone know how long the cryptarch is gonna have the old exotics available/ how long the cipher stays in our inventory or do I need to buy shadowkeep before the reset in September?