Al-Khazraji, in his book نفس الصباح في غريب القرآن وناسخه ومنسوخه, volume 2, page 683, says that
was abrogated by the regular five prayers, if
إدبار النجوم (departure of the stars) in
means the Fajr (dawn) prayer. This was reported by Ali, may God have been pleased with him. But those who believe it means the Subh (morning) prayer, such as Ad-Dhahhaak and Ibn Zayd, then it's not abrogated. Az-Zajjaaj, in his book معاني القرآن وإعرابه, said that the latter is the consensus of exegetes.
Am I the only one who notices that 52:48 speaks of sanctifying God, not of prayer? It and the next verse, recommend to a Muslim to sanctify God whenever they wake up, sometime during the night, and when the stars leave the sky. This can, and should be done in addition to the five regular prayers.