Michael has put you on the right path. The answer is very much going to depend on where your system is now and how it got there.

We need more information to offer anything useful.

What caused the displacement? Your description of moved supports and sketch suggest some kind of hammer event.

You indicate that S4 displaced East, but also that is has an axial stop. Did the stop get torn off the support?

Is the system in operation, or has it been shut down?

The shoes that fell off the supports - are they pulling back and acting as anchors, resisting the pipes attempt to return to its neutral position?

You note that the fallen off supports are "not active" - does that mean that the pipe is floating above the steel where the shoes were sitting and not making contact now?

Has the support steel been distorted? It's pretty common in the cases that I've seen of a shoe falling off due to hammering that it bends the steel when it tries to snap back into its original position.