It's possible you have faulty permissions. I am able to update a QuickBox machine with SickRage installed that is around 4 months old and the following is the Configuration info:
Database Version: 44.0
This assures us that updates are working as expected on QuickBox installations.
Please verify that you haven't adjusted permissions on your
/home/USERNAME/.sickrage directory. Otherwise, these types of complications may arise, which are in summary, of no fault of QuickBox.
For clarity, permissions should be set as follows:
Additionally, try to do a restart of Sickrage and see if your update message comes back.