Multiple administrators can have the same site page open for editing at the same time.
When you save changes to a page, the saved version will overwrite any other changes saved by any other administrator, whether before or during your editing session. If another version is overwritten – other than the version you opened for editing – then a message will be displayed informing you that you have overwritten a newer version of the page.
Versions saved by other administrators are stored in the changes history for the page, and can be viewed or restored.
If another administrator deletes the page during your current editing session, a message will appear stating that the page was not found when you try to save your changes.
The deleted page is stored in the trash, and can be viewed or restored.