Remember that warning you saw when you combined two InDesign documents? It asked, "Are you sure? This cannot be undone." Well, the truth is, it can be undone. But if not done properly, it will create a bigger problem.
Removing the Pages
1. With the combined document open, open the Pages panel.
2. Double-click the page or multi-select each of the pages that were combined accidentally.
3. With them selected, click the Trash icon at the bottom of the Pages panel.
4. Click Yes to confirm deleting the pages.
Restoring the Previously Combined Page
1. Navigate to your tcms_purged/(something_com)/Adobe InDesign Documents folder. Inside there, navigate to the specific folder for the publication and date of the pages you are trying to recover.
2. Open the Backups folder.
3. Right-click on the page that was combined accidentally and choose Cut.
4. Navigate up one level, back to the correct date folder where all the date's page are stored.
5. Right-click in an empty area of the window and select Paste.
6. Right-click on the shortcut/alias to the page that you just deleted and delete the shortcut. It will look like all the other files, except it will have a shortcut icon at the beginning of the filename and possibly a different file extension at the end — depending on the operating system you are using.
7. Right-click the file you just pasted and select Rename. Remove the _BU from the end of the filename.