Tony is offering two repayment plans to Phil for a long overdue loan. Offer 1 is to receive a visit from an enforcer and the debt is due in full at once. Offer 2 is to pay back $3,500 at the end of the year at an interest rate of 23% until Phil pays off the loan principal. Phil owes Tony $15,000. How long will it take for Phil to pay off the loan if he takes offer 2?