Hi everyone.
I’d like to report a bug in sorting of the TV shows episodes.
I have all of my specials episodes named correctly according to TheTVDB site, i.e. specials have episode numbers as in the “Episode Number” column. For example S00E01, S00E04, etc.
All of my episodes were recognized by Plex correctly and have the “Originally Available” dates correctly set.
I want the specials to be played according to the original aired date, for example I want the special episode S00E04 played after season 3. Since Plex always displays special episodes in the Specials folder and won’t play the episodes in the order I wanted, I decided to use the “Hide Seasons” advanced option for this show.

Now, all the episodes are displayed without the Seasons folders, as intended. If I set episode sorting to “Newest first” in the advanced settings of that show, the episodes will be sorted correctly (descending) according to original aired date, i.e. special episodes are placed where they chronologically belong, between the seasons.
Here is the problem - if I set episode sorting to “Oldest first” (ascending, this is what I want), the episodes are sorted by seasons not by aired date - all specials are listed first (season 0), then season 1, 2, etc. The originally available date is ignored.
To sum up - sorting by “Oldest first” doesn’t work properly.
I don’t know if this is the server problem (v1.9.4.4325) or the players’. I tested this in Plex Media Player for Windows (v3.26.2), for Linux (v3.20.6) and in Plex Web App (v3.20.7).