In Saudi Arabia, if Ramadaan commences one or two days before South Africa, a person who commences his Ramadaan in SA and spends Eid in Saudi Arabia would fast only 28/29 days. Similarly, if a person commences his Ramadaan in Saudi Arabia and upon returiing to SA before Eid, if the moon is not sighted after the 29th fast, he would have fasted 31 days.
Answer
In the first situation, if Ramadaan commenced in Saudi Arabia two days before South Africa, the person should make Eid with the people in Saudi Arabia and later make-up for one fast. In the second situation, he must keep the 31st fast and make Eid with the people in South Africa. (Ahsanul Fataawa vol.4 pg.433)
and Allah Ta’ala Knows Best
Mufti Ebrahim Desai