@Luke - I have a show that just started a new season, and strangely in the server web client Season 2 was displayed first and Season 1 second.
I tracked this down to the format of the season sort name changing. The first season has a sort name of "0001" and the second season has a sort name of "Season 2", I edited the sort name of season 1 to "Season 1" and now it sorts correctly.
All recently added seasons have this alphanumeric sort name (e.g. new shows like Believe, The 100, Resurrection) - whereas all prior seasons have the four digit numerics.
This may be a problem for everyone when the new seasons kick off in September unless some kind of rescan can change the format of all the old ones.
I tried to find another example: "The Americans" just recently started season 2, and the sort names there are "0001" and "Season 2" but in this case they appear in the correct order in the web client. Interestingly though - the field "Season number" is blank for season 2, but populated with "1" for season 1.