[aruanan]

Those aren’t high altitude clouds in the distance either. Far from 39k ft high.

Their appearance is more typical of higher altitude clouds than not. And they are at a relatively high altitude because they are still brightly illuminated while everything else out to the horizon is in shadow. The displacement between the two bands is due to distance between them east versus west not to altitude.

[TigersEye]

We'll just have to disagree about that. I don't think they look like high altitude clouds at all. Yes, the different bands of clouds are separated east to west but they exist in different atmospheric layers that extend across the sky.

Face it, your explanation is as reasonable as mine and there is no way to prove either one with certainty. It's a stalemate.