4Z 554 then 4Z 923 at Johannesburg
Durban → Johannesburg → Cape Town
Timetable, Johannesburg time
12:254Z 554 from Durban at the gate
12:204Z 923 to Cape Town leaves the gate
23 h 55 apart on the timetable, overnight
4Z 923 leaves 23 h 55 after 4Z 554 arrives on the timetable: more than half a day, so not a connection we count.