Early this month, Fallon Carter was on the phone with a client working through a series of “what ifs.” Carter, who runs an event planning company in Manhattan, wanted to reassure a bride getting married in Anguilla next May that, should her guest count plummet, her bases were covered.

“Part of my business now is figuring out whether people can travel, and what to do if they suddenly can’t,” she said. It is one of several new areas of expertise for Carter, who specializes in destination weddings, since the onslaught of the delta variant.

As the new and highly transmissible strain of COVID clamps down on the hospitality industry, planners, couples and venues are once again scrambling to make sense of how — and whether — to move forward with weddings, including many that were postponed because of the virus in 2020.

“It’s on everybody’s mind,” Carter said. That includes a couple she’s working with who called her in a panic three weeks before their Aug. 27 wedding for 175 at Blue Hill at Stone Barns in Tarrytown, New York.

The celebration was supposed to be indoors — “a nice air-conditioned moment in August,” Carter said — but with delta on the rise and the news that Gov Andrew Cuomo would start asking private businesses to require vaccinations for admission, the couple got nervous. A spur of the moment shift to an outdoor tent is underway. “Now I’m reconfiguring the dance floor and deconstructing all the floor installations.”

In Santa Barbara, California, Amy Nichols, the founder of Amy Nichols Special Events, is bracing for something even more disruptive. “As an industry in general, we’re seeing more couples who are hesitant to book for 2022 because of the delta variant,” she said. “They don’t know what to expect, whether we’ll be in better shape or things will get worse.”

The lack of a COVID crystal ball may be why some vendors are leaving nothing to chance. Daniela VillaRamos, a New York City officiant, is not asking couples and their guests for proof of vaccination. But she is attaching a hard “yet” to that policy. “If the delta variant rates continue to exponentially grow as the weather cools and weddings begin to be held indoors, we may begin requiring it,” she said. “It’s important for everyone to remember that we’re human, too.”

Nichols is working with couples who aren’t shy about asking that all vendors and guests be vaccinated. And Carter has gotten good at using Vow Digital Health, an app started in April that creates a centralized system for showing proof of vaccines or negative COVID tests. Guests get a text message asking them to upload their ID and the required documents. When it’s go time, Carter has that information at her fingertips and can admit or turn away attendees accordingly. (So far, she hasn’t had to add bouncer to her resume.)

Despite the raging variant, which prompted the CDC’s recent recommendation that all Americans, regardless of vaccination status, wear masks indoors in most of the country, asking for proof still feels uncomfortable to some. Brides like Mariah Hughes of Bangor, Maine, would rather use the honour system.

“I think I’ll be able to make an educated assumption about whether my family and friends are vaccinated,” she said. Hughes and her fiancé, Stephen Cormier, had planned to be married in September but pushed their date to next June because the photographer they wanted to work with was booked solid. They are less frustrated than relieved. “With the delta variant so prevalent, we feel like we made the right decision,” she said.

Not that she, or anyone, can count on COVID being history next year. In Denver, Brittney Griffin, the venue director at the wedding site Blanc, is prepared to start pulling out masks again even though vaccination rates are high in Colorado. “We haven’t had to yet,” but new mandates could be coming, she said. “Sadly we’ve already been through this before, so if it becomes a requirement again, at least we’re prepared.”

Niche vendors like McKenzi Taylor, the founder of Cactus Collective Weddings in Las Vegas, may be one of the few whose business picked up because of delta. Taylor plans small weddings in remote outdoor settings.

“We’re usually people’s second choice,” she said, meaning that most couples who contact her do so because COVID spoiled their original plans. She saw a 30 percent swell in bookings with the onset of the virus in 2020. Now, business is booming again. “Unfortunately, I think we’re in a whole new cycle with delta. I’m getting a lot of calls about, ‘How quickly can we get married?’ ”

Timing may not be everything, though. “Four years from now, we’re still going to be having breakthrough infections,” said Dr Amesh Adalja, an infectious disease specialist and senior scholar at the Johns Hopkins University Center for Health Security. “It’s still going to be an issue.”

Those who have their hearts set on big indoor weddings will have to roll the dice. “I think a good way to minimize the chance of anything really spiralling out of control is if everybody is vaccinated,” Adalja said. But even then, he added, “you still have to ask yourself, ‘Is it OK if I get mild symptoms?’ Because if you’re vaccinated and get a breakthrough infection, it’s unlikely to be severe.”

Which may not be consolation to anyone banking on a perfect wedding day, according to Carter. “People are like, ‘What are we gonna do?’ ”