Hello,
I realize it's over two years since the original post, however I just encountered exactly the same problem with BESR 2010. I had just done a fresh install of BESR 2010 on two Win Server 2003 servers over the weekend. They ran their first baseline at the conclusion of the install and then were scheduled for M,T,W,H,F evening incrementals. When I logged into each of these this morning I received the mysterious blue pop up about running missed backups (ignored it) and when I checked status and progress they were both hung "updating history".
For the first server I ran through the steps outlined in Symantec Document ID: 307406 (Basically delete history & schedule files, recreate backup job, start over). The second server, after at least an hour, seems to have finished its history updating and showed a fully complete status. The Symantec document indicated that this problem can happen as a result of corruption of the history file. I do hope this does not prove to be a recurring issue.