Is there a way to rewire a wire junction or re-layout a pipe junction?

I’ve noticed that changes to pipe and wire layouts are instantaneous if no new entities need to be built. For instance, this wire layout:

─────
─────

can be changed to this immediately:

──┬──
──┴──

Is the reverse also possible somehow? If I wanted to separate the two networks again, I’d deconstruct one of the middle wires and rebuild them in the right orientation, without the junction. But that can’t be the proper way to do it, right?