Carnival Cruise Line canceled cruises from all U.S. homeports except Miami and Port Canaveral in November and December, citing the U.S. Centers for Disease Control and Prevention’s (CDC) decision to extend its No Sail Order for cruise ships through Oct. 31.

The cruise line said that while operations from Miami and Port Canaveral in November and December are still not certain, its return to service will be from those ports, whenever that occurs.

“Our return to operations will be gradual and phased in,” said Christine Duffy, president of Carnival Cruise Line, in a statement. “And while we are not making any presumptions, once cruising is allowed, we will center our initial start-up from the homeports of Miami and Port Canaveral.”

Cruises from those ports will remain scheduled for November and December while Carnival evaluates options, but the line is allowing guests on those sailings to voluntarily cancel their booking and receive the same offer that all other impacted guests are receiving: a combination future cruise credit and onboard credit, or a full refund.

Carnival said it is continuing to work on protocols and procedures that would allow for the resumption of cruise operations, with a gradual, phased-in approach. In a video posted this week, Duffy said that even after the CDC lifts the No Sail Order, “it will take time for a full recovery back to our 2019 levels.”