Gmail doesn't recognize periods as characters in email addresses - their system essentially just ignores them. So if a guest's email address is <emailaddress1988@gmail.com> and the email addresses in the guest list upload file are variations of that email address with periods (e.g. email.address.1988@gmail.com, or e.m.a.i.l.address.1.9.8.8@gmail.com), the guest will receive the email invitation at emailaddress1988@gmail.com. This is not anything that Revinate has control over, but just a matter of how Gmail works.
Here is a link to an article on Google about this if you need more information.
