Is it permissible to pray Fajr in congregation and then repeat it once the time is confirmed?

Question:
One of the brothers says that the Fajr adhan here in Riyadh is before the time enters. So he prays with the congregation in the mosque and considers it a night prayer, and then he prays Fajr alone after he returns to his house. What is your opinion of his action and his argument that at the time of the iqamah, the time had not yet .

Answer:
This is doubt, waswas, and deviation from the Muslims. Pray with the Muslims, and praise be to Allah, and let there be no doubt or waswas in him. The Makkah time table is generally accurate; if it is one or two minutes early or late, that is a slight difference. This has been tested, and no major error has been found in it.
It is only seconds or minutes. But considering the Muslims' prayer to be outside the time and making up the prayer alone is deviation, and I seek refuge in Allah from that. This is waswas, and this action is not permissible. He must repent to Allah the Exalted and be with the Muslims.