(Reuters) – Democratic White House hopeful Elizabeth Warren on Tuesday said that if elected she would require employers of 15 or more to post work schedules at least two weeks in advance, in a bid to tackle unpredictable and last-minute scheduling. The proposal is modeled after a bill that Warren, a U.S. senator from Massachusetts, introduced in Congress called the Schedules that Work Act, to require employers in the food service, retail, cleaning, hospitality and warehouse industries to give employees two weeks’ notice of their work schedules. If an employee seeks a change to accommodate caring for a family member, attend training or educational classes or a second job, employers would have to accede to the request unless they provide a “legitimate business reason” why not, according to a preview of the plan Warren detailed on the website Medium. “Many employers – especially in the retail and service industries – have adopted ‘just in time’ scheduling practices that use algorithms to assign workers hours in real time,” Warren wrote. “As a result, millions of workers face work schedules that can change dramatically week-to-week or day-to-day,” she added. Warren pointed to a study of 30,000 retail and food industry workers that found 80% had “little to no input” into their work schedules. One in four said they were required to remain available for “on-call” shifts they are not guaranteed. Two-thirds got less than two weeks’ notice of schedules and half received less than a week’s notice. “Employers take advantage of that flexibility,” Warren wrote. Warren is in the top tier of 16 candidates vying for the Democratic nomination to take on President Donald Trump in November 2020. Her proposal would also mandate that companies with 15 or more employees give workers 11 hours off between shifts, compensating them extra for hours worked voluntarily in that window. It would also require that existing part-time workers be offered additional work, before hiring more employees or bringing on contractors. Warren estimates her plan would affect as many as 27 million U.S. part-time workers. It follows other proposals aimed at expanding the right of workers to join labor unions, raising the minimum hourly wage to $15 and protecting workers’ pensions.