p. 240
नीडं शकुन्ता इव जातपक्षा छन्दांस्येनं प्रजहत्यन्तकाले ॥ ५ ॥
In plain words
The way fledglings leave the nest the moment their wings are strong, the Vedas let him go at the end.
Close to the Sanskrit
As birds whose wings have grown [abandon] the nest, the metres abandon him at the time of the end.