There are currently no plans to add this feature due to the issues it presents. The current alternative is to have a Mac to remote into that can handle doing the compiling process for you, allowing you to do the rest of the packaging on the Windows machine. Unless Apple releases an SDK for another OS than OSX, the process will be at least partially Mac dependent, such as how that extension requires taking files from a Mac.
From what I understand, the extension that you linked does allow for packaging for iOS in Windows with Unity but does not allow for publishing to the App Store. I could be incorrect as I don’t have much experience with it however.