Probably AeroLogic since DHL is German owned and Aerologic is their German 777 operator.

It could be Southern too since they're probably the cheapest 777 operator with the lowest paid 777 pilots on planet earth. Maybe that's why Southern Pilots' compensation was recently "brought up" to the Atlas contract. They're still probably the lowest paid 777 pilots on planet earth though, no different than Atlas for the 76/74. It just depends on whether DHL values reliability or cost more.

They could have one of their Asian carriers like Air Hong Kong operate them too I guess, but that involve them having to start a 777 program.

It feels like I'm on the regional forum arguing over who's gonna get the next big NINE HONDO order.