Mortgage that was not protected from modification may be treated under combination of §§ 1322(b)(2) and 1322(b)(5). After debt is bifurcated under § 506(a) into secured and unsecured claims, “[t]here is nothing in sections 506(a) or 1322(b) leading the Court to conclude that the Debtor’s obligation to cure arrears under section 1322(b)(5) is [a secured] obligation in addition to payment in full of Aurora’s allowed secured claim.” “In order to satisfy the requirements of 11 U.S.C. § 1322(b)(5): (a) The Debtor’s chapter 13 plan must provide for regular monthly payments to Aurora during the term of the plan and thereafter until Aurora’s allowed secured claim of $90,500 is paid in full. The Debtor and Aurora must calculate the monthly payment amount under the terms of the parties’ existing loan agreement, as though the Debtor had not commenced this case and without regard to bifurcation of Aurora’s claim under 11 U.S.C. § 506(a), based on the full loan balance as reduced over time, taking into account the original maturity date and the then current interest rate. Aurora must credit part of each monthly payment to interest, calculated by applying the then current interest rate to Aurora’s allowed secured claim, as reduced by prior payments of principal under this sub-paragraph 2(a) and by payments of arrears under sub-paragraph 2(b), below, and must credit the remainder of each monthly payment to Aurora’s allowed secured claim until it is paid in full. (b) The Debtor’s chapter 13 plan must provide for payment in full of the arrearage on Aurora’s loan, in the aggregate amount of $21,019.08, in monthly installments over the term of the plan. Each payment of arrears under the Debtor’s plan must be applied by Aurora in reduction of its allowed secured claim. If the loan agreement and applicable non-bankruptcy law require that interest be paid on the arrearage pursuant to section 1322(e), the Debtor’s plan must provide for payment of such interest on a monthly basis and such interest will not be applied in reduction of Aurora’s allowed secured claim but will be received by Aurora as additional interest on its loan.” The deficiency claim would be treated as unsecured.