Emby has in it metadata for specials, where to show the special. Consider Battlestar Galactica as an example. If you go to season 1 in Emby, the items are shown in this order:
Miniseries episodes 1 and 2
The Lowdown special
Episode 1 of season 1
and so on
Note that the miniseries is actually season 0 episode 1 and 2, and, the lowdown is season 0 episode 8. They show however in season 1, so when you are watching the series in order, you would watch them in the correct order. In the metadata for the lowdown, Emby says airs before season 1 before episode 1. This is a very very nice feature of Emby. There are specials in this series which should be aired in the middle of seasons. Razor (a special) airs before season 4. There is a special that airs in the middle of season 4, etc.
Without this feature, one cannot easily watch a show that has specials in the correct order and it ruins the experience. Or, one has to run Emby or do web searches to figure out where the specials are supposed to be watched.
Not all specials for all shows are this way, but some are. Since Emby supports this, I would ask for Infuse to add this feature as well so that a series can be correctly watched in the correct order. Perhaps Infuse is not using the same API calls to get the order correct.