San Francisco voters are being asked to allow employees of the now-defunct San Francisco Redevelopment Agency to keep their retiree health benefits if they are hired by the city of San Francisco before March. The goal, said Supervisor Malia Cohen, who authored the ballot measure, is to prevent longtime public servants from losing benefits they earned while they worked for the San Francisco Redevelopment Agency on projects that benefited the city. Former redevelopment workers would be held to the same rules as city employees, who need five years of employment to receive retiree health benefits if they were hired before 2009, and 20 years of service if they were hired from 2009 on.