Well well well, instead of waiting in a state of continued speculation, it looks like PCMag did the hard work and went straight to RIM and got out of them the details on the soon to be released Black Berry Operating System version 4.5 update.
Updating Wirelessly (OTA)Updating with Blackberry Desktop Software on Windows Updating with Blackberry Desktop Software on Mac OS XTroubleshooting Blackberry Updates Community Q&A Blackberry releases software updates regularly to enhance the performance and functionality of its many devices.
The Blackberry Curve 8520 can either be updated wirelessly using an over-the-air (OTA) update, or using Blackberry Desktop Software on a computer.
If you use your existing Black Berry ID, all BBM contacts could be transferred from your current Black Berry device to your Dev Alpha device and they will be erased from your current Black Berry device.
You will You may attempt to load the latest Dev Alpha B update onto your Dev Alpha A, however the The Dev Alpha A is no longer officially supported as of 10.1.0.1485.
If you need to backup your device data, back it up before performing this upgrade to 10.1.0.1485.