Construction on a proposed Amazon fulfillment center at the site of the former Atlantic City Race Course has been pushed back until the spring, township officials said. The delay is because of a redesign of the proposed 3 million-square-foot facility. The project is slated to be built on a portion of the property that once featured horse stalls for the racetrack. Once ground is broken, work could take two to three years, officials have said.The project is expected to bring 750 jobs to the area, officials have said.