You can quickly add someone new to a meeting with:
/gonebusy add @mandy to Weekly Check-in
If more than one meeting matches the name you provided, you will be offered a dropdown to a select the appropriate meeting.
Likewise, you can remove someone from a meeting with:
/gonebusy remove @jody from Board of Directors
NOTE – this will add/remove from ALL instances of a Recurring meeting. We will be adding support for instances of a recurring meeting soon.