Hi sleepless in wi,
I switched your post to your old topic so it would be easier to refer back to the previous information you provided there.
Could you be more specific about what you mean by “not working” and any specific symptoms you are experiencing and the sleeping positions that are affecting them the most?
There is also more information about the most common symptoms that people may experience on a mattress in post #2 here that may clarify the types of changes that may be most helpful in terms of PPP.
Don’t forget that you “need” to sink in to some degree to provide good alignment because otherwise you may as well be sleeping on the floor without a mattress at all. A mattress that is too firm and doesn’t allow you to sink in “enough” to keep your spine in good alignment would provide poor support to the more recessed parts of your body. There is more about primary and secondary support and their relationship to pressure relief in Post #2 here and post #4 here that may be helpful in understanding what “good support” really means but the heavier parts of the body will always sink in more easily than the lighter parts of the body. The most effective way to assess whether a mattress is “working well” for you is to go by your specific symptoms and to evaluate how your symptoms change on different combinations or materials or firmness levels rather than going by how much it “feels like” you are sinking in which is much more subjective and less meaningful than your actual sleeping experience and the actual “symptoms” you are experiencing (see post #22 here).
I would also talk to Beloit to see what suggestions they may have and possibly do some additional testing there because they will also be a great source of guidance and they will be able to see you on different mattresses and hear your feedback in “real time” which is a much more effective way to decide on what to do next.
It’s very unlikely that a 36 ILD support core would be too soft for you with your weight so the “trick” will be to decide on the thickness and firmness of any comfort layers that you decide to add on top of it. I would start with sleeping on the firmer side of the mattress so you can assess how your specific “symptoms” change compared to sleeping on the mattress with the 2" comfort layer on top which may provide a more specific reference point and help “point to” the firmness and thickness of comfort layers that will work best for you. The goal is to have “just enough” thickness and firmness to provide “enough” pressure relief when you are sleeping on your side so that the risk of alignment issues is less when you are sleeping on your back or stomach. The mattress you currently have would be “inside the averages” that would normally work well for most people with your body type and sleeping positions (if anything it may be a little on the firm side) but each person can be unique and not everyone is “inside the averages” so it may take some “detective work” and trial and error to find out the layer combination that will work best for you.
Phoenix