You can join the beta with these steps:
However, I'd guess it's likely to be released fairly soon if you aren't otherwise interested in testing, so just waiting a bit more should work, too. 
For now, however, you might also want to keep the custom driver. It doesn't look like the built-in one parses power events, though the command class appears to be there for all the fingerprints the driver was written to support, so if the device doesn't do anything weird, it should be fairly easy to add (just probably not in 2.4.2).
