It would be helpful to have a feature where I could create segments based on engagement for scheduled campaigns.
When we run promos, I do my best not to email customers two days in a row. One simple way to do this is to exclude customers who opened one day’s email from the following day’s send.
In order to do this efficiently, it seems like I have to wait for the email whose openers I’d like to exclude to start sending. It’s only then that I can select it from Klaviyo’s segmentation menu.
This is true even if I make a segment with rules like “opened email once over all time where Campaign Name equals gprevious day’s campaign].” If I manually enter the name of the campaign in question, the list size will show as 0. However, as soon as that email goes out and I select the Campaign Name from the dropdown menu, it will populate accurately.
If I send promo emails 2 days in a row and I want to exclude people who opened the day 1 email from receiving day 2, I have to wait until day 1 has begun to send, then make a segment of people who opened it, THEN exclude them from the day 2 send.
It would be nice if I could make a segment for people who have opened the day 1 email before that day 1 email goes out, then let it automatically populate in the background for the day 2 send.
Long story short: help me stop working on weekends, Klaviyo! 
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