Apple is a trillion dollar company with over 160,000 employees. So when you speak 'to Apple' I assume you're speaking to Apple Support. They don't necessarily have a direct line to the iOS or iPhone developers, so the 'bad batch' is not necessarily correct and may be an attempt to mollify customers. I have worked as a software developer for similar companies to Apple so I know how it works behind the scenes.
Even if the 'bad batch' is correct, then quite often issues in the hardware can be worked around in the software. I've tried the Greek B (Apple removed my posts mentioning this explicitly) update and it looks like it has fixed the issue. Others have indicated the same. So, at the very least, it has been worked around in the software.
However, the fact that resetting the phone and doing a clean install solves the problem leads me to believe that it is a software issue related to the process of transferring from another phone. I was tempted to go down this route purely to have a clear out and remove any cruft. But experiences of the process vary, so I'm using the not-yet-released update.
HTH.