I read on CruiseMapper that Viking Bar operates 24 hours. I hope this is true as I have a 6am departure and would like a caffeine fix before heading to the airport. Here's the quote:
"Viking Bar is the 24-hour open lobby bar for specialty coffees, classic and made-to-order cocktails, gourmet sweets, and light snacks (pastries, cakes, sandwiches). Viking Bar also serves both levels of The Living Room (the Atrium lounge)."