Beast packs, specifically the Razorwing Flocks

On the charge, do they get four attacks plus one per base (making five total per base), or do they get four attacks plus one per model (making eight total per base)?

Each base has a set of stats - so the ammount of birds is not relevant. In effect the base of birds is 1 model with 1 profile.

This means you get the attacks on the profile, plus 1 for charging