Some groups, youth movements especially, have an agreement: once you take a mission you don't leave an empty spot, you find someone to fill in for you. The default JustSignup behaviour works against that, because every confirmation and reminder carries a link where a volunteer can cancel in one click.
You can turn that off per page. Open the page's editor, expand More options, and untick Volunteers can cancel their own spots.
What changes:
- The Cancel buttons disappear from the volunteer's manage page. It shows your name and email instead, with a note that your group asks people to contact you first.
- The confirmation email no longer says "change or cancel". It says to reply to the email, which reaches you directly.
- The schedule email (on pages where you assign people) says the agreement is to find your own cover.
- The reminder the day before says to reply as early as possible instead of offering a cancel link.
- The signup form's small print changes to match.
You can still remove anyone yourself from the page's dashboard or People page, and the spot reopens as usual. Volunteers can still see their signups, add them to their calendar and check in on the day.