Champion/Challenger vs A/B Test in Engagement Program Hi everyone! We are working on building our first Engagement Program, and we want to test the subject lines on the emails. I've seen conflicting info about champion/challenger and a/b and whether you can do them with batch campaigns or only triggers.Our ideal scenario: create a stream with 5 emails in it, test subject lines within the engagement program (so send out subject A to half, send subject B to half, all still within the engagement program, and see which does better). We don't want the "winner" to be sent to the people who received the non-winner because they already received the email in the stream. Half would get email 1A, half would get email 1B, and then they would just continue in the stream. Then upon next cast, half would get email 2A and half would get 2B, all the way through the 5 emails.Once we get a decent amount of people through the stream, we would then stop the testing and just use the winner for each email in the engagement program moving forward.Any i
