For scheduling I use the delay node.
Its state wont get saved right?
I thought that there might be a way to save the current "state" of a node - So that after a restart of node red, the delay node still knows for how long it is active.
I suggest that is a bad idea. Instead use Persistent Context to save what needs to be done and when, and then have a simple flow that does it when necessary. Working with context : Node-RED