As businesses struggle to adjust to an evolving COVID pandemic, Mountain View digital advertising giant Google has for the fourth time delayed a mandatory return of its workforce to offices, it said Thursday.

Google had planned to bring in workers three days per week under a hybrid model mixing office and remote employment starting Jan. 10, which would have ended the “voluntary work-from-home period,” the company said in an email.

Now, Google will wait till after Jan. 1 to determine when its hybrid-employment model of three days a week in offices will begin, the firm said. The start will depend on local conditions, which the company noted, without mentioning the new omicron coronavirus variant, are “dynamic and vary greatly across locations.”

As conditions have allowed, Google has permitted employees to come into the 90% of its U.S. offices that have been safely opened, the company said. Almost 40% of U.S. employees have made an appearance in offices, according to Google. The firm’s change of plans was first reported by CNBC.

Google’s decision comes amid a global scramble to respond to omicron, about which relatively little is yet known. At least eight new omicron cases were reported Thursday, five in New York, one each in Colorado and Hawaii, and one in a Minnesota man who had recently traveled to New York City. The first case identified in the U.S. was in a San Francisco resident believed to be fully vaccinated but not boosted.

Google has several times created then delayed office-return plans as the virus has mutated and public health orders have changed.