Update: I found a software I am using to guarantee that images are uploaded right way up, not sideways:
https://savolai.net/software/JPEG-EXIF_autorotate
---> Obvious warning, I did not develop this, and it's open source (not actively being managed), use at own risk, etc. etc.
I've been using it with great success. It basically automatically rotates images and removes the hidden iphone rotation data, so images always upload everywhere right way up.
It adds right click menu items when you click on a folder containing .jpg images:
When Installing, I recommend using these settings:
This means when it's done it will not sit there asking you to "hit any key to close this window", and will automatically regenerate the thumbnails that show in your computer to reflect the actual image rotation. (Helpful if you help your phone sideways, but the phone did not detect that it was sideways before you took the picture.)
For anyone that is having issues with image upload, this is an easy fix you can implement, as I have pretty much given up hope of resolving the sideways images at the forum software level.
JW