Workers at a duo of Trader Joe’s stores in New York City and Oakland, California, are scheduled to cast ballots on April 19 and 20 to determine whether to unionize, according to a Thursday tweet from Trader Joe’s United, the labor organization looking to represent the workers.

The announcement follows the union’s disclosure late last month that the workers had filed plans with the National Labor Relations Board (NLRB) to hold the elections and continues a drive by Trader Joe’s United to add to its small but growing membership. The union has said Trader Joe’s has mistreated workers by cutting retirement benefits, providing unacceptably low wages and not responding effectively to safety concerns.

Each of the two Trader Joe’s locations where workers are set to vote on unionizing this week would become the first store in its market to unionize if its associates decide to join Trader Joe’s United. Workers at the Oakland store recently filed unfair labor practices claiming that Trader Joe’s has attempted to interfere in their efforts to organize and threatened to take action against them, SFGate reported last week.

If the workers in New York City and Oakland decide to unionize, they would follow Trader Joe’s employees at stores in Hadley, Massachusetts; Minneapolis; and Louisville, Kentucky, in electing to formally organize. The grocery chain filed an objection to the Louisville vote with the NLRB, claiming that workers and an attorney for the union had tainted the vote.

Last October, Trader Joe’s workers at a store in the New York borough of Brooklyn voted not to join Trader Joe’s United, making the store the first — and so far only — in the California-based chain where workers have formally rejected an effort to unionize them.

Earlier in 2022, employees in Boulder, Colorado, withdrew a petition for a vote on unionization they had filed with the NLRB.