करोत्येकमहश्छेदं तथैवैकं च चन्द्रमाः ॥ कZ_०२.२०.६५च्द् ॥
karoty ekam ahaś-chedaṃ tathaiva ekaṃ ca candramāḥ
Thus, (over time) it produces a cut/adjustment of one day; likewise, the moon also (produces) one (day’s adjustment).
A formal rule for inserting/removing days to keep the official calendar aligned with observable cycles, preventing administrative disorder.