When documents are edited using the AOS the updates doesn't get reflected in the preview.
1. Edit a word document using "Edit in Microsoft Office". Start in the document details page.
2. Save you changes in Word.
3. Go to document details page. Refresh. Document is "Locked by you". Edits are not shown (expected since you still have the document open).
4. Go back to word. Close the document.
5. Go back to document details page. Refresh. Lock is gone. The preview still shows the older version. Expected: The preview will show the new version
6. Click the download button. You can see that you edits are in the document, but not shown in the preview.
Note: It sometimes shows the correct preview, so you may have to try a copule of times.
Tested with AOS 1.1.3 and 5.2 Nightly from 2016-09-27 (cirka)