For awhile there, it seemed like things were finally heading back to normal. Now, not so much.

In the span of just a week, plans for a September return-to-the-office have been pushed back. Mask mandates have made a comeback. And a growing number of employers, including the federal government, are laying down the line on vaccines.

On Friday, Walmart — the country's largest private employer — reversed its policy and will once again require all workers to wear masks in areas most affected by the delta variant of COVID-19. The New York Times indefinitely postponed its planned return to the office.

The delta variant is much more transmittable, and health officials are now concerned that it may also make people sicker and can even be spread by fully vaccinated individuals. That means, almost a year and a half into the pandemic, companies are facing a difficult task of yet again recalibrating what steps are necessary to keep workers safe.

"This is a Rubik's Cube with a thousand colors on each side," says David Lewis, CEO of OperationsInc, a human resources consulting practice. "There just continue to be a lot more questions than answers."

The CDC's reversal on masks was a tipping point

First came the reversal from the CDC.

On Tuesday, in response to the delta variant, CDC Director Rochelle Walensky said fully-vaccinated Americans should once again wear masks indoors in places where the coronavirus is surging, citing new research that showed vaccinated people can spread the virus to others.

The automotive world was ready to act. Ford said it was once again mandating masks at its facilities in Missouri and Florida, effective Wednesday. It has since added Kentucky. Earlier, General Motors was reported as reinstating mask requirements at its plant in Wentzville, Mo.

The response from Big Tech was swift as well. On Wednesday, Twitter said it was closing offices in New York and San Francisco that had just recently reopened. Google announced it was delaying its return-to-office date for most employees from September to mid-October. Google and Facebook also said they would now require employees to be vaccinated before coming into the office, a requirement Twitter already had in place.

Then on Thursday, calling deaths among the unvaccinated "an American tragedy," President Biden ordered federal civilian employees and contractors to confirm they are vaccinated or submit to regular testing. The Pentagon later said members of the military would be subject to the same rules.

Many companies are still figuring it out

Most major companies are taking a few days' pause to figure out how to adapt to the CDC's new call for universal indoor masking in some parts of the country.

"As a country, vaccination options have been available for months, but, unfortunately, because so many people have chosen not to receive it, we've left ourselves more vulnerable to variants," Walmart executives wrote in a memo to U.S. staff.

Decisions are particularly tricky for companies whose workers were never able to work remotely. Grocers and supermarkets, for example, were quick to drop mask requirements for shoppers when the CDC had eased its guidance in May. Workers there had been harassed, attacked and even killed as they were forced to become enforcers of masking mandates.

Walmart and its Sam's Club arm, for now, are "strongly encouraging" but not requiring shoppers to wear masks in stores. The company is among others, like Target and Dollar General, that have been paying workers bonuses for vaccinating. On Friday, Walmart said it's doubling the bonus to $150.

NPR has reached out to almost two dozen major retail, hotel, food and pharmacy chains. Many, like Costco and Publix, say they are watching for regulations to come from local and state authorities.

"We do work very closely and monitor the local situation and we adapt accordingly. So if it means that we have to wear masks again, even if vaccinated, that's what we'll do," Amazon's Chief Financial Officer Brian Olsavsky told reporters on Thursday.

Olsavsky did add that Amazon is "still aiming for a return to office in September," working to provide more vaccines to its employees but not requiring them.

Expect a range of responses from employers

Lewis, the HR consultant, is advising clients against rushing into decisions to postpone return-to-work plans, given the uncertainties around how the long this latest COVID surge will last. But, he says, communication is key.

"Tell your employees what you're thinking and at least give them a sense that you're paying attention," says Lewis.

As with every stage of the pandemic, what employers ultimately decide to do will vary greatly by industry and by region.

One size does not fit all, he says, and no decision is simple. Companies that do choose to reinstate masks, for example, run the risk of stirring up greater levels of resistance among employees who may already have concerns about coming back to the office.

This week, as the number of new COVID-19 cases continued to soar, a sense of exasperation could be felt all across the country.

"It is truly unfortunate that mask recommendations have returned," the National Retail Federation said on Tuesday, "when the surest known way to reduce the threat of the virus is widespread vaccination."

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