Rotation of an image is stored in the exif data.
When you take an image with your phone in a non upright position the phone will rotate the picture to look like you expect it and write into the exif data.
But the image itself will still be the way it was taken, meaning the data of the image itself is unaltered.
Usually when you send the picture or upload it software will read the exif data and display the image accordingly (rotated). But some sites or some software will ignore or strip the exif data and display the image how it originally looks (non-rotated).
I don't know the previous owners, I just was told that when she was handed in, she was quite injured and took a couple of weeks for her to recover. Because of this, her listing said they recommended a home without any existing cats.
She's a year and a half old and was handed in a couple of months ago, so I'm assuming they did have her for about a year before they decided to hand her in, but again, I only know what the staff at the pound told me.