I just found this post in CC by user @thecruiserofships (thank you to them) in the Carnival section.......
It looks like Carnival is getting close to releasing Carnival Luminosa sailing itineraries/dates for bookings. The docking space is now reserved for Seattle sailings and a couple dates have appeared in the Carnival Hub App. The tentative cruise dates from Seattle are as follows:
May 2023; 4, 11, 18, 25
June 2023: 1, 8, 15, 21, 28
July 2023: 6, 13, 20, 27
August 2023: 3, 10, 17, 24, 31
September 2023: 7, 14
http://www.embarkandaway.com/general-cruise-blog/carnival-luminosa-2023-alaska-cruises
https://claalaska.com/?page_id=1250 (primary source of the above dates - includes other port docking calendars too)
Most of the Seattle dates are departures on Thursday to sail what would be 7 night cruises. There is at least one 6 day and one 8 day mixed in. The Carnival Hub app currently shows November 6, 2022 and May 4, 2023 which could correspond to the first Brisbane date and then the first Alaska cruise from Seattle date.
With docking space reserved and work starting to take place on the Carnival Hub App, hopefully it won't be too much longer before the Carnival Luminosa is open for bookings. I'm personally curious to see what work the ship gets (and does not get) since there will be a minimal amount of time for Carnival to make updates to the ship......