There is nothing in the numbers you indicated to cause concern of any sort - it is pretty much the norm for even healthy people, and usually is associated with the phase of falling down into sleep or shortly before waking in your case, most likely. It can also indicate a shift from one sleep state to another, and is perfectly normal when is does not make up the majority or a large minority of your nightly report. We all have it, and all healthy people have both central and obstructive apnoeas as well, so don't let the numbers game get to you. The idea of 0% AHI is really a silly one, and being the infinitely interesting and occasionally breakable complex creatures we are, bits of all sorts of odd things crop up, even in our sleep.
Instead of worrying about numbers on your report, give as much time to how you feel so much better as you can. That is the real truth here. A bit of Periodic Breathing is well within the norm, and while I am sure you'll have tons of questions for your doc in May (and you should - pepper the bugger with questions, that is what you pay him for - to answer them and make sure you understand how to manage your health), in the meantime, enjoy the new found feeling of energy. And raise a glass to the Aussies while you're at it, because without a clever doc there, you wouldn't have a CPAP to make you feel better. Good on yer, Skip!