I remember having this discussion during playtesting with Naturalist way back when, and maybe I'm just remembering wrong, or maybe this is a change in the ruling. If I'm in Gazelle, and I play Bestial Shift, and use the bonus power to change to Rhino or Croc, then I also get their effect; no problem there. However, my memory is that even if you start in Croc, if you use the bonus power to change forms, you can "go back" and get the benefit of your new form. Essentially, the ruling was, "the one-shot is still out, so you can still get those effects". Like I said, it was widely discussed during playtesting, but that's the ruling I remember. However, in the game, it just goes strictly in order.
So, bug? Or did the ruling change? Or did I remember it wrong?