Comment by andrewflnr

Well, if it's tidally locked (which it probably is and the paper doesn't disabuse me), then both its rotation and orbit are about 8 hours on the sameish axis. So it's still spinning pretty dang fast, enough that the gas doesn't have to settle into hot and cold sides. I can't fully parse the part of the paper where they talk about the wind structure, but they do seem to think it still has some banding. Section 5: https://iopscience.iop.org/article/10.3847/2041-8213/ae157c (linked elsewhere, here again for convenience).