Day and Night Shifts For Angels?

Narrated Abu Hurairah:

regarding Allah, Most High, saying: "And recite the Qur'an in the early dawn. Verily the recitation of the Qur'an in the early dawn is ever witnessed (17:78)." The Prophet (ﷺ) said: "It is witnessed by the angels of the night and the angels of the day."

https://sunnah.com/tirmidhi:3135

Note: The Arabic in the quotation has 'the Fajr quran', as though this were a separate quran.

A quran?

'This' Quran