Losing my mind

I'm going crazy trying to remember a specific activity. Ever since the dreadnought was announced to be coming back I kept thinking it already had in the past, but I could be wrong. There was a seasonal/limited time activity that took place on (from what I remember) a hive ship. It was either crashed, or we boarded it. There were things we had to find there for either a seasonal quest, or exotic. It was a patrol area from what I remember and it had an ongoing activity where we were fighting hive and it would pop up in like 3 different areas in this one big room where we'd have to fight waves of enemies and move onto the next (similar to season of the Haunted on the leviathan). You could also explore a bit, but not a ton because alot of it was blocked off. Like I said the exploration i think was mostly to find pieces of something, etc for a quest. I swear this existed but cannot find anything about it online. Please help 🙏