Tail textures flipping upside-down

[HappyDaize Resident]

I've run into an interesting issue...

I have had the tail texture flipping from day to day, on the same cat. One day her tail texture is correct, the next it is flipped upside-down. It's very obvious on this Aussie fur when it happens, since the top side should be tabby striped and the underside is a creamy white.

Here are screenshots of her with the tail correct, and with the textures when flipped. Not sure what causes it, but it varies from one day to the next.