The phrase "next years" refers to the upcoming or future years. It implies a time period that is yet to come, usually within the near future. Full definition
Even if everything goes your way, it's going to take many months if not years of extremely hard work and sacrifice to get where you want. (inc.com)
Taking those excess funds and putting them directly toward student debt can knock off months if not years of payments by reducing the principal balance and ultimately, the interest. (studentloans.net)
I'd give it at least several months if not years before trying some sort of «fasting» again. (paleoforwomen.com)