We've changed the warning that shows when modifying the repeat settings of an appointment. Doing this causes all the existing appointments in the series to be deleted and recreated based on the new rule. For a group appointment, this means that all the patients booked into those appointments will be removed. This wasn't clear before.
We've also added this warning when choosing to apply changes to future repeats. We are planning to change how this bit works in the near future. We want it to be possible to change the practitioner, notes, and other basic information for all repeats in a series without deleting and recreating them. Until we're able to that, we're including this warning so it's clear what will happen.