still called 11
Well to be honest 11.31 has little in common with 11.00, but even 11.31 was 2007. I think they canned 11.41 years back. Some marketing zeeb decided that SW vendors didn't like the major release number changing so they decided to just keep calling it HP-UX 11 for ever, 11.00 -> 11.11 was a bigger kernel change than 10.20 -> 11. Same with 11.11 to 11.23 and yet again with 11.23 to 11.31.
Didn't Sun do something similar with Solaris, weren't they all 2.X for years?