^^ Once again, you are not going to like my response, TDHXIII:
Respectfully, I am pretty sure that there is no state of "auto SP."
I'm actually far more than "pretty sure," because that knowledge is based on much more than personal opinion. For one, if you were to experience actual SP (auto or not), you would do so upon
waking up, and not upon falling asleep. Also, you cannot "break out" of SP, period; they do not call it Sleep
Paralysis for nothing... indeed, if you ever want to prove to yourself that you are in SP some morning when you might awaken ahead of your body, just make an effort to move: in actual SP, you cannot move in any way, so your effort to move, or break out, will fail.
What you are experiencing is probably some onset of perfectly normal REM Atonia as your body goes to sleep. Everything you described above sounds very much like HI, and, once again, you really would do well to ignore it and stay focused on your upcoming dream.
A couple other things as well:
You perhaps should have waited a bit longer, because if REM atonia is noticeable, then you were indeed on the threshold to your dream. Next time, instead of waiting, pass the time by focusing on your dream, or perhaps moving right into it yourself: for instance, if you sense that your body is asleep (that REM Atonia or "SP state" sensation) try "rolling out of it" with your dream body.
All these things seem to represent times when your body might be inclined toward getting to sleep a bit faster than your mind, so you could indeed be noticing REM Atonia, or at least extreme relaxation, because your mind is still active while your body sets about sleeping (that's a fine time to WILD, BTW). Once again, your body is not dragging itself into paralysis, it is settling into sleep, and sending you signals that it needs some rest. And yes, if you lay down in a relaxed state long enough, you will fall asleep, even if you never intended to do so.
I know my point of view about SP, though based on experience (both mine and many others) and scientific knowledge, is not very popular here, but I hope you will take a minute to listen to me,. Placing concepts like "auto SP" in your path only hurts your chance to WILD, even if you think otherwise. The popular SP myth, in my opinion, has created an artificial barrier to LD'ing, and not a bridge to it, so I will continue to suggest that people do what they can to ignore the on-line hype and choose to understand that all those sensations they feel on the way to sleep are things that happen
every time your body goes to sleep, only this time you are there to witness them. Let REM Atonia and all that HI join the ranks of
noise to be ignored rather than goals to be achieved, and your WILD's will be easier to achieve and much, much more common.