The overall rating reflects the current state of the app. It accounts for all app reviews but prioritizes the most recent ones.
I'm not sure why this app has 5 stars. I asked for help and they basically told me to upgrade for a better experience. Emails are not delivered immediately (I had to contact customer service each time and they manually pushed them through on their end). You can't even see your click/open rate without upgrading. I was hopeful but I'm truly disappointed. The search continues!