What if I don't want the helpers to all be notified when there is a schedule change?

Normally when you make a change to a Published schedule the affected Helpers who have chosen to be notified are sent an email about the change.

When making changes to a Published schedule, you also can choose whether to send the affected Helpers a notice about the change or not.

On the Schedules screen, or on the popup you are using to make the shift change, there is a checkbox for "Send notices to affected Helpers" that if you uncheck before saving your change. the Helpers are not sent a notice of the change.