Get each particle position from update particle.

Hello, what i want to achieve is having a blend between 2 position for each particle. I got the position for each particle on a skin mesh, and i would like to blend it with the result of the "commit to sphere" node for exemple. My problem is that i can't blend between the two. When i'm putting a blend position node between the skin mesh particle and a "commit to sphere" in update there is flickering. Basically having two set position in update is causing conflict.

That's why i'm trying to store the position of each particle from the update system somewhere to then doing a blend. My question is basically, is it possible to store the position of each particle somewhere after the update system.
Thanks !