Many of the indivduals we are sending our email campaigns to have multiple email addresses (either a personal and work, or a work email and an assistant, sometimes multiple assistants, etc.). Before, we were able to send the same message to up to three different email addresses under one contact, by labeling the emails as "work", "home" and "other".
Now that Constant Contact has updated and changed their contacts to only having 1 email address per contact, we are unable to properly reach our intended audience.
This significantly reduces the functionality of Constant Contact for our business and we have already started looking at other options.