Ohh, I didn't realize that Kullervo's Hold is a time limited event. Have they said before how long it's gonna go up or if it's going to repeat?
Looking forward to getting new reasons to go back to duviri, I do like the new content but it felt kinda lacking when it comes to rewards. Hopefully this improves it a bit.
I'm not sure it's an actual time-limited event, like the previous Operations.
I believe they mentioned in the devstream that the lost island would only be around during certain spirals, so hopefully that's what they mean. If it's a real limited time event, I don't think they said how long.
As others might have explained, the "event" which lasts a couple weeks will grant access to the Kullervo prison island regardless of the current spiral. After the event is over, and on normal runs, the hold will only show up on certain spirals and not others, similar to Archarbor