Cloth pinning dynamically to pin and restart the simulation

Hello,
i made a text deflation and inflation animation with cloth pressure.

The goal of it is to deflate the whole text and then start the simulation one letter at the time. I have set up the dynamic vertex group with proximity modifiers and mix all of them with the weight mix modifier.

The thing is that i use it as a pinning group and if the weight is 1 after the mesh got deflated for 30 frames it resets the positions of the verts to the original at frame 1.

Not sure why it is…