Re-queue a contact who has already received the series

I understand that once a contact has received an email or an automation once, they won't recieve it again, even if they are removed from a list and then added back on. However, this is a problem for me because I cannot continue to test whether automated series are working if I made a change to them or a change to how they are generated/connected thru my website because I've already tested it out before.... My request is that the email for the account be allowed to receive the emails repeatedly for testing purposes or some other work-around. Hope that makes sense. Thank you, Laura