user receives email notification even though restriction have been applied to the page

Steps to reproduce :

1. Login to Confluence
2. Create a page
3. Insert a team calendar into the page
4. Ask a user A to watch the page
5. Make changes to team calendar
6. User A is receiving email notification for the calendar as expected
7. Creator of the page restrict the page with the calendar from being viewed by the user
8. Creator of the page make changes to the calendar again within the page restricted from User A
9. User A is still receiving email notification for the calendar changes even though restriction have been applied to the page

Expected behavior : User A should not receive notification for the calendar from pages that have been restricted

Current behavior : User A is still receiving notification from the page with the calendar even though the page have been restricted.

Basically this happen because User A that have previously watch the page have been restricted from it is still receiving email from the calendar updates from that restricted page.

The workaround would be to remove User A from the watcher list of the page after restricting the page which is not really ideal if you have a large amount of user watching the page.