Can I still play the Season 17 story/activities to get older loot?

I’m a returning player from season 16. I bought the standard edition of the Witch Queen back when it came out and have been considering getting the upgrade to Deluxe. This will net me season 19, the WQ Dungeon Key, and season 17.

I’ve been wanting to go back and play season 17 and get all of it’s loot since I know it was damn good for Solar builds. Is it still possible to play the main quest line and the primary activities?