Sympathies. I am 2.5mo post-takedown and I rely entirely on narcotics (I find oxycodone works better than hydro in my case) to get more than two or three hours in a row. It's a simple equation for me: when I use it, I sleep six hours +/-1. When I don't, my nights are just like yours.
Setting aside for the moment whether long-term narcotic use is a good idea, or whether your doctor will allow it (more on those topics below), does hydrocodone really zonk you out so much that you fear "sleeping through a BM"? In my case, there's no chance of that. On 10mg, I sleep well and comfortably, but when the pouch strikes, I'm wide awake. This is even true on the few occasions where I don't make it 6h. Have you had other accidents?
So here's a suggestion: Get yourself some Depends and/or chucks (disposable "water"proof pads) to sleep in/on, and try it for a couple of nights. You may surprise yourself.
Now, IMHO, the stigma associated with long-term narcotic use is overblown and unwarranted when used to slow digestion. As I understand it, whereas the pain releiving and psychotropic effects diminish over long usage, the digestive effects do not. And, again IMHO, addiction is irrelevant when a medical need exists - though there's little risk of developing an addiction if you're only using it once or twice a day. This all assumes you are lucky enough to have a doctor who agrees and is willing to continue prescribing narcotics long-term.
I will also echo notes from this thread and others: Make your last meal of the day a small one, and eat it at least 4h before bedtime. Take a motility reducing drug (Lomotil, Immodium, tincture of opium) up to 1h before bedtime. Use psyllium fiber (e.g. Metamucil) to thicken, slow, and de-sting-ify. (NB: I found it is possible to overdo the psyllium. I was using the "tablespoon dose" powder, 1Tbsp 3x/day: the extra volume caused extra BMs, which is obviously counterproductive. At this point, I use capsules, four before each meal, with much better results.)
Next: sleeping position. I'm right there with you. I go longest when I sleep on my back. I had to learn this and get used to it - I also prefer side-with-knee-pillow. One thing that helped here: Yoga. Most yoga classes end with a position called Savasana. To the uninitiated, this looks like "lying on your back". But (as with all yoga) the subtleties of the positioning have been carefully studied and tuned over generations. To wit, I have always had trouble with limbs falling asleep, joints aching, etc. during sleep; in a proper Savasana, I don't. (I usually don't even need a pillow.)
However, I have noticed that you can fight it and get used to it. It used to be that I couldn't lay on either side at all, even for a couple of minutes. But I have found more and more that, if you ignore (okay, fight off, fists clenched and teeth gritted) those first few waves of cramps/urges, sometimes, if you're lucky, they'll fade and disappear for long enough to get you some rest. In my case, if I get a real good empty, I can usually get a few hours on my left side. Right side seems slightly worse, but probably no statistical significance.
I think this one is going to depend on the exact configuration of your specific pouch. My theory here is that it has to do with the way the pouch deforms and stretches depending on your orientation: in some positions, it may squeeze to a reduced capacity; it may tug on your anastamosis; it may increase contact of stool with spots of irritation (especially in your pouchitis case).
Pushing: ye gods, don't do it. I struggle so hard with this (so to speak). I spent my whole life with tenesmus (though I didn't have a name for it until my diagnosis), so I have decades of pushing habits ingrained in my brain. Even now, with the diseased colon gone, I have tenesmus - never feeling empty, thinking if I can just push hard enough, I'll get there.
This is poison. This will cause a vicious cycle that will delay your recovery and could lead to other complications. It may even be the cause of your pouchitis. Here's my (non-medical, anecdotal) explanation: When you push, you cause the tissues to become inflamed. Inflamed tissues are more sensitive, and will result in greater feelings of urgency from any pressure or contact from gas or stool. It doesn't take much until the inflammation can cause urgency all by itself (without pressure/gas/stool). You respond to the urgency with more pushing, and so on. The pushing and inflammation can (and will) lead to hemorrhoids and similar structures at any point along the pouch and exit route. Now you have stool coming in contact with open wounds. Infection (which may be diagnosed as "pouchitis" in some cases) becomes a question of when, not if.
Believe me when I say that this is the hardest part of my recovery: the utter iron-willed discipline required for me NOT to push. Especially when I'm experiencing tenesmus, which I still do, regularly (no pun intended). You will become frustrated because you'll FEEL like you should push, and you'll discipline yourself not to, and then you'll get up, and the urge will hit again right away, and sometimes you'll actually even produce. "See - there WAS stool there - I just wasn't pushing." To break the cycle, you need to ignore these "secondary urges". It will only take a few days for them to subside. In the meantime, ask your doctor for some hydrocortisone/pramoxine cream to help with the inflammation.
Best of luck to you. I'll be following your case with interest.