I've seen this issue with linking pupils to parents via the Control Panel (and Parent Portal Manager). I assume this is a generic feature within Control Panel.
When you link a pupil to a parent's user account, you get the attached warning message. An explanation via the Helpdesk explains that the following holds:
If the pupil is already linked to the parent account, he/she remains linked.
If the pupil is not already linked to the parent account, he/she becomes linked.
As far as I can tell, the warning message applies to the first possibility and, reading between the lines, it sounds as if, technically speaking, an error is generated in the background and the pupil is removed and then re-added.
However, the message is just causing confusion here and doesn't seem to imply that any actions should be taken by the end user. (The result of one's actions are exactly as one would expect in either case.)
It would be great if messages like this only appeared if there are consequential actions to be taken.
Hi Sarah, the warning is to highlight that any existing PP accounts linked to that pupil will be impacted. The wording however is not great and its something we will be updating in the near future.