Here is an attempt at representing a two-photon enganglement situation as analyzed in spacetime for two observers (red and black in sketch below) moving in opposite directions at the same relativistic speeds with respect to the black rest system shown in the sketch. Let's say that the photon moving to the left is found to be in the UP state at event A by an observer at rest in the red frame. Then the photon moving to the right snapes to the DOWN state at event B. I have the following puzzling questions: 1) If the right photon is in a DOWN state at event B, then in the blue coordinate system that would seem to snap the left photon into an UP state at event C. But that event precedes event A, implying a reverse causality, that is event A has caused the past event C. 2) Once event A has snapped the left photon into UP, how does nature decide which observer's frame of reference to snap the right photon into? The black reference frame would have the right photon snapping to DOWN at event D. 3) Would a chain of events be released, i.e., event C causes the right photon to snap to DOWN at event E, etc.?