DOCSP-37408 Rollover Requirement (#283)

* DOCSP-37408 Rollover Requirement

* Fixes per Evgeni

Author: kennethdyer

source/reference/api/reverse.txt

@@ -43,6 +43,9 @@ To use the ``reverse`` endpoint:
 
   You cannot update these options after the sync starts.
 - ``mongosync`` must be in the ``COMMITTED`` state.
+- The destination cluster oplog must not roll over between 
+  ``mongosync`` reaching the ``COMMITTED`` state and receiving
+  the ``/reverse`` request.
 - :ref:`index-type-unique` require proper formatting.  Collections with indexes
   initially created on MongoDB 4.2 may not have the proper formatting.