May not be a player here but I have had that happen with pictures I took with my iPhone (turned sideways for landscape view) and then posted to web. I tried to fix it the original photo in a photo editor by rotating it then reposting it and it still was upside down. The problem was always in landscape mode holding my iPhone sideways. I turned my iPhone the other direction for another photo and repeated the up load and the problem went away. May be something about how the iPhone saves the image that makes it want to treat the landscape shots differently according to how you hold the phone. If your photos came from an iPhone or even some other brand, you may want to turn the phone in a different direction and try again.
Paul D
Paul Davidson