Problem
If you rename a group, space permissions are updated to reflect the new group name, but page restrictions (different to permissions) are not updated. The page restrictions will remain in place despite the old group no longer existing, which could potentially cause members of the renamed group to be locked out of pages.
Solution
Currently there is no mitigation for this problem built into CSUM. Investigation into a permanent solution is ongoing (see CSUM-65 - Getting issue details... STATUS for more details). In the meantime a manual approach is suggested as per the below steps.
Fix page restrictions via SQL queries
Follow the following Atlassian guide in order to rename each of your groups which contain upper-case characters: https://confluence.atlassian.com/confkb/how-to-rename-a-group-and-preserve-its-permissions-948228977.html
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