Add a new rule to the ruleset.  Call it “Jam Session” and give it the following text:

As a weekly action, each Musician may either start a Jam Session or Join an existing Jam Session.  To start a Jam Session, a Musician posts a Story Post with “Jam Session” in its title.  To Join a Jam Session, a Musician makes a comment to that Jam Session’s Story Post stating that they are doing so.  A Musician who has started or Joined a Jam Session is a member of that Jam Session.

Band Members cannot start Jam Sessions. A Musician cannot Join a Jam Session if that Jam Session has ended, if they are already a member of that Jam Session, if they are a Band Member or if a member of that Jam Session has a Grievance against them.

As soon as is practical after a Jam Session has been posted for 48 hours, the Frontman shall end that jam session by making a comment on its Story Post saying that it’s over.  If the Jam Session has three or more members, he shall then inform each member of that Jam Session of the style of a random other member of that Jam Session.