Sleep study advice needed (2nd titration study)

I will have my second titration study at the beginning of March. I have gotten the TAP III and this will be the titration study, though there's no titration in the usual sense of the word (no changes in pressure since there's no cpap, just the dental device). It's to see if the TAP III is working or not. I want to make very sure that it's a good study that shows me what I need to know about how well the TAP III is working. They are also looking for UARS.

Here is the main issue as I see it: In my original study I had more apneas during supine sleep and during REM sleep. So there are three possible conditions that could be measured during this study.

1. REM during back-sleeping only (I am not on my side at all during the REM cycles)
2. REM during side-sleeping (I am not on my back at all during REM cycles)
3. REM during both side-sleeping and back-sleeping

I want to make sure that I find out about condition 3, where I am side-sleeping during at least one REM cycle and where I am back-sleeping during at least one REM cycle. This is very important to me for TAP use, since I will have no machine that will measure my AHI each night as I do with my REMSTAR auto. This will tell me if I need to stay on my side all the time when wearing the TAP or if I can sleep both on my side and my back when wearing it.

It's not likely that I will use the TAP exclusively, but I would like to have it for camping, traveling, when I'm sick, when my nose is sore, and power outages. I have some idea that it is working (I turned my pressure down to 4 and did side-sleeping and got decent results on my REMSTAR Encore software).

I have never been able to train myself to sleep on my side exclusively. Tennis balls and a pillow-stuffed backpack didn't do it. I have been able to achieve side-sleeping all night by using a backpack stuffed with a large fabric-filled shoebox. I am willing to use this if need be, but it is rather uncomfortable and I wake up with aches and pains due to not moving positions during the night. So, if I have to side sleep whenever I use the TAP, I need to know so I can arrange it. If I don't need to, I think it will be much easier on my body.

I am working with a good sleep clinic this time, but it is associated with a large hospital (they are also testing me for UARS). My concern is what to request so that I can make sure all conditions are tested adequately. I might be able take my side-sleeping contraption and start out with that, then once I get a good REM cycle on the side, have the tech awaken me and take it off and move onto my back. I am a pretty sound sleeper so I am not too concerned about going back to sleep for a (hopefully) second REM cycle. I know not all REM cycles are equal, but that can't be changed as far as I know. Plus, I don't know what the test needs to look like to test the UARS.

Not so easy to arrange this I'm guessing, but I likely need to talk with my doctor soon to make sure it's set up right in advance so there's no question for the techs if it's different from their standard operating procedure.

Any thoughts about what I've outlined (flaws in the theory or process), tips about dealing with the sleep techs at the study, with my doctor beforehand, etc. If anyone, particularly anyone associated with sleep medicine, can comment, I'd welcome it greatly.