The following says the BB2 has digital dry through: BeatBuddy: 2
Why would the BB need to convert the guitar audio to digital and then back? This is not a pedal that processes the input guitar signal. It’s effectively a mixer that can add the drums to the guitar.
Perhaps there’s a future feature that will take advantage of the digital audio? Maybe something that listens to the audio and plays a matching beat? Maybe a simple looper?