Health IS Wealth review for Mailchimp Email SMS Marketing

I was able to install the app and complete the sync without any problems. My biggest concern is that my email list DOUBLED in size and now I'm left wondering where all of the extra subscribers came from. Are they real subscribers or people that previously unsubscribed? Or did I get random emails connected to my list? My business reputation is on the line and I will be sending an explanatory email to all of my customers regarding the new integration with ShopSync.