(DOCSP-40136) Removed unsupported AppDB backup method.

Author: corryroot

source/tutorial/upgrade-om-version.txt

@@ -27,8 +27,14 @@ Prerequisites
    - Your ``gen.key`` files to a secure location. The :ref:`gen.key <gen-key>`
      provides details to encrypt and decrypt |onprem|\'s backing databases
      and user credentials. |onprem| might delete these files as part of the upgrade process.
-   - Your :ref:`application database <appdb-om-arch>`. If the upgrade fails,
-     you need a current backup to restore your |onprem| instance.
+   
+   As an extra precaution, you may use :dbtools:`mongodump 
+   </mongodump>` to create a binary export of the 
+   :opsmgr:`Application Database 
+   </reference/glossary/#std-term-application-database>`. No officially 
+   supported backup method exists for the Application Database. If the 
+   upgrade fails, reach out to |mdb-support| for help fixing the 
+   issue with the |onprem| version.
 
 1. Upgrade |onprem| by following the considerations, prerequisites, and procedure in :ref:`upgrade-om`.