I've had sleep paralysis hundreds of times.. just trying to be helpful lol. once i switched to my side i never got it again.. but feel free to peruse some of these sources and hope this helps

A large study done on sleep paralysis: J. A. Cheyne Department of Psychology, University of Waterloo https://onlinelibrary.wiley.com/doi/full/10.1046/j.1365-2869.2002.00297.x " It is widely believed that lying in the supine position is a proximate cause of sleep paralysis. "

https://en.wikipedia.org/wiki/Sleep_paralysis#Prevention "Sleeping in the supine position has been found an especially prominent instigator of sleep paralysis."

https://sleepbetter.org/sleep-paralysis-the-scariest-sleep-disorder/ "It’s believed that supine sleep (sleeping on your back) can make a person five times more likely to have an episode of sleep paralysis than any other position. "

https://www.nhs.uk/conditions/sleep-paralysis/ " It's not clear why REM sleep can sometimes occur while you're awake, but it has been associated with sleeping on your back"

https://www.sleepcycle.com/sleep-paralysis/what-is-sleep-paralysis/ "Avoid sleeping on your back. Research shows that sleeping on the back can be linked to increased risk of sleep paralysis."

https://www.verywellhealth.com/what-is-sleep-paralysis-3014777 " It more often occurs while sleeping on one’s back."

https://www.verywellhealth.com/what-causes-sleep-paralysis-3014700 " Sleeping Position. Most people with sleep paralysis report that it occurs when they are sleeping on their backs (a supine sleeping position)."

https://www.webmd.com/sleep-disorders/features/sleep-paralysis-demon-in-the-bedroom#2 " Don't sleep on your back. Sleep experts have found a correlation between sleeping in a supine position and being vulnerable to sleep paralysis. "

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