Without deciding whether § 1325(b) applies at modification after confirmation, plan can be modified to pay unsecured creditors in full in 60 months, notwithstanding that debtors have additional disposable income that could be used to pay unsecured creditors more quickly. After confirmation, debtors proposed to surrender real property and pay a portion of the freed-up income to unsecured creditors. Unsecured creditors would be paid in full in 60 months with less than all available income after surrender. “The Winns’ proposed modification will pay all allowed claims in full; thus, it meets the Section 1325(b)(1)(A) confirmation requirement. While the modified plan does not propose to pay all of the Winns’ projected disposable income to the plan and fails to meet Section 1325(b)(1)(B), this criterion need not be met. . . . [Section] 1325(b)(4)(B) . . . states that the ‘ “applicable commitment period” may be less than 3 or 5 years, whichever is applicable under subparagraph (A), but only if the plan provides for payment in full of all allowed unsecured claims over a shorter period.’ . . . [I]t appears that a plan that provides for payment of all allowed unsecured claims may be completed earlier than the full length of the plan, but this is by no means necessary.”