I forgot about maintenance today! My friends just told me earlier too! I was uploading videos from today's fun experiences and my bro was duoing Normal Imperial City Prison. I bet they could've completed, but it is like fun, and I am glad I came to help because they might not have finished before maintenance! And I never turn down the chance to help out on a Normal Dungeon!
Here is the video of our experience!
https://www.youtube.com/watch?v=VL0gnKOzqJE&t=6s