Function to test the best time to send out a campaign

Description: A function to test the best time to send out campaigns. 

Why is this feature important to you: be relevant for the customer and get higher open and click rates. Also, to improve the email sender's reputation. 

How would you like the feature to work: a function to divide the audience and send the e-mail at 2 or 3 different times/ days. The test will be sent out to a small part of the audience, the winner will be sent out to the rest of the audience.  

Current Behaviour: no functionality to test different times or days to send an email.