Coca-Cola is delaying plans to return thousands of workers to its Atlanta headquarters, as the delta variant continues to shake up job expectations at Georgia employers large and small.

The beverage giant told local employees Monday that they won’t be returning to corporate offices until mid October at the earliest. That’s more than a month later than previous plans to bring workers back starting Sept. 7.

Like a number of large companies in Atlanta, Coke had sent most of its local workers home early in the COVID-19 pandemic more than 18 months ago. Some major employers began office returns over the summer, but a big wave had been expected in September.

Now, a number of employers are quickly shifting plans as coronavirus cases surge and hospitalizations increase, with the virus spreading mostly among the unvaccinated.

Midtown Atlanta-based Invesco, a global investment management company with about 1,000 local employees and 8,500 worldwide, told U.S. workers late last week that they will be required to show proof of being fully vaccinated before being allowed back in its offices. Spokeswoman Jeaneen Terrio said Invesco’s U.S. office returns are still slated for no earlier than Sept. 13, but the company is closely monitoring coronavirus developments.

As for the vaccination measure, she said, “Our first priority is to ensure the health and safety of our employees as we continue to serve our clients. We felt that was the appropriate step to take.”

Coke’s note to employees about its delay of office returns cited “the significant increase in COVID transmission rates in the Atlanta area.” The company added that, “Effective immediately, only approved employees will have regular access” to the Atlanta campus, where about 3,100 people are based in normal times.

Georgia Power recently pushed back return plans for some office workers indefinitely. Cox Enterprises, which owns broadband and automotive services businesses, as well as The Atlanta Journal-Constitution, said it will require that employees who enter its headquarters and certain other offices be fully vaccinated against COVID-19.

And Home Depot said it has begun requiring its more than half a million employees nationwide to wear masks while indoors in its U.S. stores, offices and distribution centers.