(3:05 p.m. EDT) -- More than 30 Royal Caribbean cruise itineraries have been altered in response to a propulsion pod issue on Allure of the Seas. The problem has caused the ship to sail at reduced speeds, prompting itinerary changes.

In order for ports to accommodate Allure's new schedule, tweaks were also made to voyages for some of the line's other ships. Among them is Oasis of the Seas; Cruise Critic boards member normannna, who is booked on the ship's December 8 sailing, received a letter informing her that the planned ports of call have been moved to different days.

"The itinerary modifications were due to a technical limitation on one of the ship's propulsion pods which lowers the maximum speed," Royal Caribbean said in a statement.

"As a result of the slower travel, we must modify 30+ itineraries. Since we had to change Allure's itineraries, some ports would now have more ships than originally planned. So, to ensure our guests have a wonderful time in each destination with less crowds, we've rearranged the order some of our other ships will be visiting some of our destinations."

Royal Caribbean has not yet said when the propulsion issue will be fixed, but Allure of the Seas' next scheduled dry dock is set for March 2020.