Is there any way to edit the orientation of an image?

[eyerhymes]

Any time I try to submit an artwork in any orientation, the preview and the submission revert to landscape. I can't find any option to change this during the submission process, or afterwards. I've even tried rotating the image that I want to submit into all four possible orientations on my end before submitting, but all four revert to the same incorrect orientation.

I have lots of art I'd love to share, but there's not much point if it's going to be displayed incorrectly.

If I'm just blind, or if anyone knows a fix, I'd love to know. Thanks in advance!