The .btag.it tracking method is a legacy feature. Although this feature is still functional, we recommend users set up their mail clients with our SMTP Relay Tracking method. Setup instructions for the SMTP Relay are available on our Help Center.
No, the .btag.it tracking method is limited to one recipient per email.
Also note that sending one email to a recipient with the .btag.it extension and another recipient without the .btag.it extension in the same email will cause the delivery to the .btag.it recipient to be rejected. (The other user will get the email.) If that recipient replies to all, then their message to the address with the .btag.it extension will be rejected, unless they have a Bananatag account.
Only use the .btag.it tracking method when sending to a single recipient.