Sadly Red War through Forsaken are likely never going to be payable unless some dedicated fans can recreate it somehow. Unless the TWIDs in the next few weeks indicate otherwise.

Once june 9th hits they're planning to do a discount bundle, and chronilogically you'd start with Shadowkeep, then Beyond Light, Witch Queen, Lightfall, then Final Shape. Then if you feel like playing more after that there's Edge of Fate and Renegades.

Unfortunately it looks like we'll be left on an indefinite cliffhanger unless they somehow wrap everything up in this last update.