When cruise lines first announced they would stop sailing in response to the pandemic in mid-March, companies called it a “voluntary and temporary pause” that was initially expected to last 30 days.

It’s still a question when cruising, at least in North America, will resume, but one thing is clear: That once-temporary pause will stretch over more than a year as operators work to meet public health requirements and mobilize a global workforce.

“If I was planning a 2021 sailing, I would wait,” said Stewart Chiron, a cruise industry observer and CEO of the site cruiseguy.com. “Because I don’t know which ships are going where, when and for how long.”

This week, three large cruise lines announced a fresh batch of canceled cruises. Carnival Cruise Line, which had earlier stretched its pause to the end of February, is extending the cancellations until March 31. Princess Cruises, which had been on hold until March 31, moved the date to May 14. And Holland America Line, which had canceled trips through March 31, has extended to April 30.

Last week, Norwegian Cruise Line suspended all cruises through March; it had previously left sailings on three ships on the books. And while Royal Caribbean International and Celebrity Cruises have only canceled trips through the end of February, it would be impossible for them to resume by mid-March given the timeline of requirements by the Centers for Disease Control and Prevention.

According to an order issued in October, any cruise line that wants to restart from the United States needs to apply for a conditional sailing certificate 60 days before a voyage. But before that happens, they need to run test sailings with volunteers — and must provide written notice 30 days in advance.

The CDC said this week that no cruise line had applied for a certificate yet.

“Essentially since the CDC’s no-sail order expired at the end of October and upon revealing their new directives, which are almost impossible to follow, April is the earliest they’d be able to resume,” Chiron said. Even beyond the health and safety measures, cruise lines will have to get crew back on board, quarantine them and retrain them, he said.

Mike Driscoll, editor in chief of the industry newsletter Cruise Week, said the travel retailers he has been surveying recently have said they expect cruising to resume any time between May and December. Most, he said, are looking at June — and they expect to see a lot more cancellations in the meantime.

“They’re saying it’s later than the cruise executives are now,” he said.

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