Princess Cruises said the Regal Princess, a ship under construction, will arrive 13 days ahead of schedule, enabling the line to add two cruises.
Regal Princess' first cruise had been scheduled for June 2, but Princess has bumped that up to May 20.
The new maiden voyage will be a seven-day cruise from Venice to Athens with stops in the Greek islands of Corfu and Mykonos and an overnight call in Istanbul.
A second cruise will depart May 27 from Athens and spend six days calling on Kusadasi, Turkey; Santorini and Katakolon, Greece; and Dubrovnik, Croatia, on its way to Venice.
Passengers previously booked on the June 2 maiden voyage have until Nov. 15 to decide whether they want to take the new cruise instead of, or in addition to, their existing reservation.
Regal Princess will carry 3,650 passengers and is a sister ship to Royal Princess, which debuted earlier this year.Follow Tom Stieghorst on Twitter @tstravelweekly.