do we have the opportunity to test send out time in Default or Engagement program?
Or is this just possible for list import program?
If it's just possible for list import: how could we do it in a program based on a smart list?
Date/time testing is only available in email programs, not champion/challenger testing which is used by Engagement and Default programs.
If you would like to test different send times in a default program you would need to split your audience into two lists and use two different smart campaigns scheduled for different times to send the email to each list. You can do the split a couple different ways: manually or using the Random Sample filter or choice.
For engagement programs, since the cast time is controlled by the stream's cadence, you would need to setup two streams with the same content and assign each one a different stream cadence. Then when you add people the program you would use the random sample choice to divide your audience evenly between the streams.
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