EBF baby sippy cup or bottle?


My boy is almost 9 months old and is EBF he would never take a bottle but unfortunately I have to return to work in a month or so and I need him to take something I feel it's too late for a bottle that I should just try a sippy cup but i doubt he will take that either. Just looking for advice would you recommend bottle or cup? and any advice on how to get him to take one