SA 281 then SA 347 at Johannesburg
Perth → Johannesburg → Cape Town
Timetable, Johannesburg time
05:05SA 281 from Perth at the gate
17:30SA 347 to Cape Town leaves the gate
12 h 25 apart on the timetable
SA 347 leaves 12 h 25 after SA 281 arrives on the timetable: more than half a day, so not a connection we count.