Canon EOS 80D - Manual (Page 310)

3 Setting the Movie Recording Size
310
 Movie Shooting Time Limit
The maximum recording time of one movie clip is 29 min. 59 sec. If
the movie shooting time reaches 29 min. 59 sec., the movie shooting
will stop automatically. You can start shooting a movie again by
pressing the <0> button. (The movie will be recorded as a new
movie file.)