After months of planning, a big wave of metro Atlanta workers was finally slated in the coming weeks to roll back into corporate offices for the first time since the pandemic began.

But the the surging delta variant, Georgia’s lagging vaccination rate and new federal guidance and local directives to wear masks indoors are injecting major uncertainty into those plans.

Many large employers, including Coca-Cola, UPS and Home Depot, prepped for new September arrivals at their local headquarters, timed to follow kids returning to public schools in August.

Georgia Power decided in recent days to put its September return plans on hold indefinitely, citing rising COVID-19 cases involving the new variant. Other employers also could delay returns.

“A more conservative posture” will help protect employees while “we see where this variant goes over the next few weeks,” Chief Executive Officer Chris Womack told The Atlanta Journal-Constitution on Thursday.

Several big companies said they were monitoring the shifting stances from public health officials and government leaders.

Employers also could implement more restrictive policies for those office workers who do return.

Before the latest coronavirus surge, many companies didn’t plan to require proof of vaccination. Under an honor system, vaccinated office workers would be allowed to roam without masks or social distancing, while unvaccinated colleagues would mask up.

Some employers, including State Farm and Georgia-Pacific, recently expanded their masking requirements in big offices to include everyone, regardless of vaccine status. Georgia Power is considering the same.

While frontline workers haven’t had the option of working from home, many office employees have been doing their jobs remotely since March of last year. Office access swipes are just 35% of what they were before the pandemic, based on data from 10 cities, according to controls company Kastle Systems.

Employers have been navigating a minefield of polarizing issues, wanting to keep employees safe while considering privacy concerns, avoiding legal entanglements and weighing business needs. Companies also are adapting to increased employee interest in working from home and trying to keep workers happy in a tight labor market.

As COVID-19 cases surge, though, recent federal guidance and rulings are giving employers more confidence about what they can legally require of their staff. That includes mandating that employees disclose whether they are vaccinated and requiring vaccinations as a condition of employment, with certain exceptions, said Jennifer Sandberg, regional managing partner for employment and labor law firm Fisher & Phillips.

“I think we will see more employers asking about vaccination status, and I think ultimately we will see more employers requiring the vaccine,” she said. “From a business perspective, it’s the easiest and quickest way of getting back to business as usual.”

But she also predicted that some companies will further delay office worker returns.

On Tuesday, the Centers for Disease Control and Prevention changed its guidance, calling on even vaccinated people to wear masks indoors in places with substantial or high transmission rates. That includes nearly every county in Georgia, where the vaccination rate lags that of most states.

On Wednesday, Atlanta Mayor Keisha Lance Bottoms mandated that people, regardless of vaccination status, wear a mask in the city when indoors in a public place, including private businesses. On Thursday, President Joe Biden announced plans to require that federal government workers undergo weekly testing for the coronavirus unless they are fully vaccinated.

Caleb Stubbs, a 27-year-old engineer who works in Midtown, said most of his colleagues already are required to be back at the office, with some pandemic-era plastic partitions still in place in shared cubicles. As of a few days ago, most weren’t wearing masks.

“I’m perfectly comfortable with it being an honor system,” Stubbs said at the time, a mask looped around one arm for easy access. He was still required to mask up on MARTA.

Courtney Bond, a 26-year-old who works as a case manager at an Atlanta law firm, said she quit another firm a few weeks ago. She had complaints about the earlier job, including low pay, but the last straw was when the firm tried to make her get the vaccine, she said. Employees at her new firm aren’t asked about vaccinations and weren’t wearing masks as of a few days ago, she said.

But many local offices, particularly of large companies, remain virtual ghost towns.

In the latter half of July, the number of elevator trips logged in metro Atlanta offices was only half what it was before the pandemic, according to engineering company Thyssenkrupp. The figure is even lower — just 38% — in offices with a city of Atlanta postal address. And unlike in the past, local workers say when they ride elevators these days, they are nearly always alone.

Many workers who are back are on hybrid schedules, working from home some days and the office on others.

Office returns have picked up over the summer, with some additional employees going back at a number of businesses, including State Farm and Delta, which says that 87% of its headquarters staff is fully vaccinated. Some are holding out longer. IHG Hotels & Resorts said it expects to welcome all its employees back under a flexible work strategy in the fall, according to a spokesperson.

A number of state government employees are back in their offices. At least on paper, Gov. Brian Kemp has banned the state government from requiring proof that state employees have been vaccinated.

Trey Loughran is ready to get more employees back in the office at least some days each week at Purchasing Power, a local company where he is CEO. He said people have been productive, but that company culture has suffered under remote work.

Many are slated to return on a hybrid schedule in September. Given the CDC’s latest guidance, he is expanding a mask requirement to everyone in office common areas.

The entire staff also has been invited to the company’s 20th anniversary celebration. For now at least, it is still scheduled for early September in a Georgia Aquarium ballroom. Loughran is hoping many choose to show up.

“It will be the first time we will all be back together again,” he said. “I can’t wait for that.”

— Staff writers Greg Bluestein, Ben Brasch and Tyler Estep contributed to this article.