For general population studies (i.e. Women in New York) expect videos to roll in same day.
However, if you're running a study with hard-to-reach demographics (i.e. Tax Accountants over 40 years old in the UK) please allow a few business days.
You will receive an email when the first video is received and when the study is complete.
Other factors
Testing an unreleased mobile app (such as a Test flight link) will take longer