Johannesburg is 8 hours ahead of Austin during US summer (CDT), and 7 hours ahead during winter (CST). When it's 9:00 AM in Austin, it's 4:00 PM or 5:00 PM in Johannesburg.
South Africa uses SAST (UTC+2) year-round and doesn't observe DST.
Optimal window: 7:00 AM - 9:00 AM Austin time (3:00 PM - 5:00 PM Johannesburg). Early morning calls from Austin catch afternoon business hours in Johannesburg.
Connecting flights through major hubs link Austin to Johannesburg O.R. Tambo International Airport.