LOS ANGELES – Chad Billingsley just might re-join the Dodgers rotation before Clayton Kershaw does.Billingsley begins a minor-league rehab assignment Sunday for Class-A Rancho Cucamonga and said he has five starts planned. After that, the team might activate him from the disabled list. That could put him on track for a return right around May 6.Billingsley had Tommy John surgery last April."I'm using this as a spring training, fine-tuning mechanics and working on my pitches.