Of course one has to wonder just what kind of testing they do when they didn't even notice the continuity issue to begin with.
The testing is likely to be all automated (i.e. unit tests), but as it takes several week for the firmware to go through testing, I'm guessing they might have a few units that they use to verify the performance (to make sure an update doesn't invalidate the specifications). I think the bug with the continuity was missed as it couldn't be detected through automated testing, and I seriously doubt they have someone who sits in front of a unit of each model and checks the features manually. But it is very disappointing that a new version of the firmware hasn't been released - let's hope it doesn't take them as long as it did to fix the histogram update bug (which was roughly a year).