The way I noticed how things are arranged in this database is that everything has it own entry, given that the title is somewhat different. For example, if we were to take Attack on Titan, technically it ran for two seasons straight, and the third one
is coming. The third one, if it were to change, like if a subtitle was added to the title (Attack on Titan: Titans revealed) then that would get its own entry. However, if there was a AOT short OAV that came out, it would have to have its own entry, because
it isn't part of the series.
So, I think Silver Spoon 2 should have its own entry. And all Break Blade movies should have their own entries as well.