When you create email and turn into an a/b test (right click on the email, select a/b test) does this format work for nurture programs? if not when is this useful?
Yes, it works in a nurture program as well
It is used for Nurture Engagements and Trigger campaigns only.
But does it work with Engagement Programs or only with Engagement Emails?
Champion Challenger is for Emails and this type can only be added to Trigger flows or Engagement Streams.
If you use a Program nested in an Engagement Stream, then no, you cannot use Champ/Challenger. You should use the Random Sample flow step instead.
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