Copy Proc Mesh from Static Mesh (Spline Mesh)

So. I have this:
Spline Meshes are hidden In Game.

Then I use Event Begin Play and setting up the parameters of Spline Mesh (updating the mesh too). After all the thing is done I use Copy Proc Mesh from SM component but get nothing, I mean nothing I’ve changed (End Pos, Start Scale, End Scale, Start Tangent) is not applied. I get a Proc Mesh copied from Spline Mesh raw with no edits. Where my mistake may hide?

I guess the problem is UE Proc Mesh doesn’t generate in blueprint realtime and should be used in Construction Script only. Isn’t it?