I'm not sure it does anymore? According to https://en.wikipedia.org/wiki/LauncherOne https://en.wikipedia.org/wiki/LauncherOne, White Knight Two was originally

I'm not sure it does anymore? According to https://en.wikipedia.org/wiki/LauncherOne https://en.wikipedia.org/wiki/LauncherOne, White Knight Two was originally proposed to launch LauncherOne rockets, but then in 2015 this was changed to a 747, to carry a heavier rocket. The White Knight Two derivative by Stratolaunch is much bigger (https://en.wikipedia.org/wiki/Scaled_Composites_Stratolaunch https://en.wikipedia.org/wiki/Scaled_Composites_Stratolaunch).