SA 538 then 4Z 763 at Johannesburg
Durban → Johannesburg → Upington
Timetable, Johannesburg time
10:20SA 538 from Durban at the gate
10:154Z 763 to Upington leaves the gate
23 h 55 apart on the timetable, overnight
4Z 763 leaves 23 h 55 after SA 538 arrives on the timetable: more than half a day, so not a connection we count.