Hi Colin, tks for you contribution here!
I've checked logs and didn't find any info on "log system" looking for the date when I tried the upgrade (nothin was registered for 29-Feb and 1-Mar). There is no info at "log upgrade" showing not avaiable/incomplete and "show image" shows the new image as backup.
Backup build date looks strange when comparting to current image as showed below.. not sure if this means something.
Primary Partition Build Time :2015-04-05 02:10:58 PDT
Backup Partition Build Time :PST-00-Nov 22 16:41:06
Evidences are attached, if you find something please let me know.
Tks