This is a common mistake.
Most people don't realize that as well as Windows 3.1, and Windows for Workgroups 3.11, there was also Windows for Workgroups 3.1 and Windows 3.11 (without networking). That's four products. Windows for Workgroups 3.1 was extremely rare, but I'm sure I saw it or saw it mentioned somewhere.
Microsoft also did a number of unnecessary Win32s upgrades aimed at beaking OS/2. It became a cycle: IBM made it work, so Microsoft made a minor release that broke OS/2, so IBM found out what they'd broken and released a patch for OS/2, so Microsoft made another minor release, etc. IBM eventually gave up, though it would have fun if they'd kept at it just to show the press how dastardly Microsoft was being.
Wade.
"All around me are nothing but fakes
Come with me on the biggest fake of all!"