Mobile homes were only covered for ten years from the date of manufacture. The eleventh year was available to make claims for leaks during the original ten years. Your unit is almost three years past its deadline, so the class action no longer applies to you. Your situation is the very reason I tell anyone who has the PB piping to tell their neighbors as soon as they discover that they have the piping. If that had been done, the original owners would have had it replaced.