EPR and Weight Loss Affecting Mask Seals?

[Snooks]

I've been on CPAP for around 15 months now and I have always used the Resmed F20 FFM. Early December it was needing the silicone cushion replaced so I bought one and I endured issues with it hurting the top of my nose and also at night it would move and the bottom of the silicone mask would be in my mouth, I would wake up with a very dry throat and of course I had massive leaks. I swear the mask was smaller but the evidence shows it isnt. They even replaced it with another mask but the same thing happened so the problem is certainly mine and not the mask as such.

I put this down to a substantial weight loss over the previous 6 months by diet and exercise as I have taken off 31kgs (70lbs). My face is now far skinnier and i think the structural change has made that mask very hard to use. I replaced it with an Evora FFM but thats a different thread (lol)

So I also tried using the EPR Function to aid with Flow Limitations but the instability got even worse. It seems that using EPR1 the strap tensions were fine but on expiration the mask tension would be looser and the mask would move. On EPR2 it was even more evident. I turned the EPR back off and the mask seals improved though are still not what I would be happy with. I felt that I had to have the mask straps way too tight.

Is the EPR known to affect mask tensions and cause seal issues or is that just me thinking desperately because I am annoyed and concerned about the major seal issues and results that I have been getting for the last couple of months or so? Once I get the mask(s) well controlled I will try the EPR again but just wondering if anyone else notices that the strap tensions change during the inhale /exhale etc.

Thanks