Starbucks has called on employees in three Northeast locations to reject a measure to form a union, following a victory by a Buffalo-area location that’s spearheading efforts to organize its workers.

The company, which just last week announced plans to hike wages for its U.S. employees, sent a letter on Monday encouraging those workers to vote down a measure to organize. If the effort is successful, three coffee shops in upstate New York would be the first of Starbucks’ 8,000 stores to unionize, part of a wave of pandemic-era support for organized labor.

“We want you to vote no,” wrote Allyson Peck, Starbucks’ Northeast regional Vice President, in a letter shared with Yahoo Finance.

“There’s a lot going on. We want to talk about and connect on the union vote and what it means and doesn’t mean for you, because it has a potentially big impact on your job and your store,” the executive said in the letter.

“Unless you are positive you want to pay a Union to represent you to us, you must vote no. There is no opt out if the majority of voters vote yes, regardless of how you voted,” Peck wrote.

Last week, the National Labor Relations Board sided with workers, rejecting Starbucks’ attempt to hold a single vote with 20 stores in the region.

Mail-in voting is scheduled to start next week, and will run through December 8, with a final vote count on December 9. There are about 128 employees at the three stores that will vote, according to the NLRB decision.

In a statement on Thursday, the Seattle-based coffee giant said it’ll be reviewing the ruling and be evaluating its options.

“We remain focused on supporting our partners as well as maintaining open, transparent and direct conversations throughout the process. We just received the ruling, and we are evaluating our options,” the company said.

'Very significant' decision

Michelle Eisen, an 11-year Starbucks barista in Buffalo and a member of the union organizing group, Starbucks Workers United, is happy about the NLRB’s ruling.

“It was very significant and it wasn't unexpected,” Eisen told Yahoo! Finance Live on Monday.

With her decade-plus experience at Starbucks, Eisen has been at the forefront of the unionization effort, however, since the NLRB’s decision that came out last week she’s noticed “drastic changes” in her work environment.

“They have upped their interference by at least a percentage,” said Eisen, who accused Starbucks corporate officials of interfering in the effort. But according to her, “thousands of partners from across the country have reached out to our organizing committee asking how we got started, what steps they could take in their area to follow suit.”

That also included workers high up in the chain like regional directors and district managers, Eisen added.

The NLRB’s decision came the same day Starbucks came under pressure, after the company told investors that its fiscal 2022 outlook would be weaker than expected. The global coffee chain blamed rising costs and the ongoing impact of the pandemic.

Nevertheless, Starbucks has been forced to bow to realities of a tight labor market, and announced plans to raise its average pay to nearly $17 an hour by summer 2022 in a bid to attract and keep baristas amid the labor crunch.

Linking it to the ongoing union fight, Eisen called the pay move “great.”

She added: “They are adding seniority pay to the wages, which is something that has come up in our campaign,” said Eisen. “The timing on that was not great [but] we knew what it was in response to.”

Meanwhile, the decision underscores U.S. workers’ intensifying push to improve stagnant pay and working conditions following years of decline for organized labor. This also follows a spate of strikes that have rocked the private sector, revealing the new power workers wield as the pandemic exposes the strains in a stressed-out labor force that’s quitting jobs at historically high rates.

In response, hourly wages at some of the largest corporations — including Chipotle, Target and Amazon — have received pay raises.

In other words, we’re in a time where workers have a once-in-a-generation upper hand.

“People are turning down jobs that they just see as not suitable and a lot of people are re-evaluating what they want to do with their lives,” Todd Vachon, director of the Labor Education Action Research Network at Rutgers University, told Yahoo Finance in an interview.

While Starbucks was hoping to open voting to the entire Buffalo market in a single ballot, Vachon suggested that the move was strategic.

“It's to their benefit, to include all of the other stores where workers haven't decided whether or not they want union yet, because it waters down the pool of voters,” he said.

Even though the move didn’t work, Vachon believes the workers have a chance to unionize once the votes are counted.

“If the workers in those three stores said they want to have an election, they're pretty confident that they have a majority of support,” Vachon said.

“You wouldn't want to go to the NLRB and start an election, unless you're pretty sure you're going to win it,” Vachon added.

Dani Romero is a reporter for Yahoo Finance. Follow her on Twitter: @daniromerotv

Read the latest financial and business news from Yahoo Finance

Follow Yahoo Finance on Twitter, Facebook, Instagram, Flipboard, LinkedIn, YouTube, and reddit