4/6/2016 8:19:13 PM
I can confirm, several filmmakers submitted their short film to me for airing on TV right after they completed it, before they submit for festival circuit. Result: in many cases their film was declined, because it was no longer a 'premiere'. Airing the short film on TV before going to festival basically short-circuited its festival run.
As SonnyBoo points out, upload or stream you film after all festivals screened it!