Debtors with CMI greater than applicable median family income can modify five-year plan to pay off plan in single payment four years early when modification otherwise satisfies § 1329. One year into five-year plan debtor’s parents agreed to gift the full amount necessary to pay off the plan conditioned on court approval of the modification. “[Section] 1329 does not incorporate § 1325(b), and thus a chapter 13 plan may be modified so that it has a term shorter than the applicable commitment period, so long as the plan as modified satisfies the other requirements of § 1329 . . . . Because § 1329(b)([1]) references only §§ 1322(a), 1322(b), and 1323(c), and the requirements of § 1325(a), it ‘excludes other provisions.’ . . . To determine that § 1329(b)(1) incorporates § 1325(b) because of the introductory text in § 1325(a) referring to § 1325(b) ‘collides with the rule that statutes should be interpreted to avoid redundancies,’ as doing so would cause § 1329(b)(1) to incorporate § 1322(a) twice, once directly and once as a result of reference to § 1322(b) which also refers to § 1322(a). . . . [T]he Bankruptcy Code does not require that a modified plan have a particular minimum term. . . . Congress provided some leeway in how a modification may be structured, and that leeway includes shortening the term to less than the original applicable commitment period or even to a single payment.”