The Messenger of Allah ﷺ said, "The Quran was revealed in seven modes. Whichever of them you recite is sufficient for you."
إن رسول الله ﷺ قال: نزل القرآن على سبعة أحرف، أيها قرأت أجزأك.
Ahmad narrated it (27443) from Sufyan, from Ubaydullah, from his father, from Umm Ayub, and he mentioned it.Its chain is hasan because of the father of Ubaydullah, who is Abu Yazid al-Makki, the ally of Banu Zahra. It is said that he had companionship with the Prophet. Ibn Hibban graded him trustworthy (7/657), and Ajli said, "A trustworthy successor." Tirmidhi said, regarding a hadith other than this one that he narrated, "hasan sahih gharib."Through this route, Humaydi recorded it (340), as did Ibn Abu Asim in Ahad wal-Mathani (3320). Ibn Kathir mentioned this hadith in Fadail Quran (p. 64) with the chain of Ahmad and said, "Its chain is sahih."I say, perhaps he graded it sahih on account of its corroborating narrations.