When a user reverts a page to an old version from Timeline of Sites, the order of sibling pages changes, unintentionally. This issue happens only with the members of a particular group. Not with admin.
The user/group has insufficient read permission to the sibling pages. The version keeps and tries to restore the order of sibling pages for which the user
can recognize. If the order is A - B - C and a user has read permission only on B and C, when the user saves a version of C then revert to the saved version,
AEM will restore the order of B - C first and does not care about the order for A. As a consequence, the sibling order may become B - C - A.
Grant read permisson to all sibling pages. To avoid user to see the page contents which are irrelevant, add ‘Deny’ of
jcr;all rep:glob=*/jcr:content/* on each
sibling page node (the node of
sling:resourceType = cq:Page). The user can recognise the existence of the sibling pages (and the child pages of the sibling pages)
but cannot see the contents of those.