Custom unsubscribe group

[Mapteg34]

Hello.
We use plugin with version 1.11.8.
We use it with wp_mail mail function (redifined on plugin), and all work fine, but we receive new task:

some mails need to send with custom unsubscribe group.

Yes, we can reconfigure it in plugin options. But in this way every mail sends with it. We need some only.

Yes, we can define SENDGRID_UNSUBSCRIBE_GROUP before wp_mail call. But we cant undefine SENDGRID_UNSUBSCRIBE_GROUP after call. And if wp send any other emails after out mail - they are sent with this constant. Not fine.

No, we not have any way to tell wp_mail send only this mail with this unsubscribe group.

Can you add it in you plugin (i.e. add sendgrid_unsubscribe_group_id in $headers of wp_mail)?