There is a 20 hour per month streaming limit on StreamYard's free plan. There are no streaming limits on StreamYard's paid plans, but keep in mind most destinations have their own limits.
The limits are:
-8 hours on Facebook (profiles, pages, groups)
-No limit on YouTube (though only the last 12 hours will be recorded)
-4 hours on LinkedIn
-48 hours on Twitch
-4 hours on Twitter