What is the ruling on delaying the Dhuhr prayer in Algeria beyond its true time throughout the year, and is one who prays it with the delayed congregation, not having prayed it at its true time, sinful, and what should one do in this case?

The time for Dhuhr is expansive, and the difference mentioned is not significant; thus, this delay is not a delay from the beginning of the time. If you do not find a congregation praying at the beginning of the time, then you should pray with the later congregation, because the virtue of congregational prayer takes precedence over praying at the very beginning of the time. However, if you find a congregation at the beginning of the time, even if small, then it is better to pray with them to combine the virtues of both congregational prayer and praying at the beginning of the time. Praying with the later congregation carries the virtue of congregational prayer, along with the possibility of it occurring before the time if its commencement is not certain.