At its Newark hub, meanwhile, United is also delaying the launch of new non-stops to Johannesburg from March 27 to June 3 as South Africa copes with the rapid spread of a new coronavirus variant. Delta is also delaying its introduction of Atlanta-Johannesburg-Cape Town flights from March 27 to June 1.
https://www.sfgate.com/travel/article/Delta-SFO-OAK-United-delays-JFK-India-Cathay-15950648.php