There was one line from the Big Bad Evil Guy in Ghostbusters 2 that I liked enough that it inspires my own version: "Time is but a window. Space is but a doorway. I shall return."
We're already playing fast and loose with causality. Prime example: I'm going to have it that Benjamin's appendix rupture (which, IRL happened circa 08/2019) occurred prior to his employment with Funthom Industries. Why? So when he faces off against Guaron during the St. Valentine's Eve Massacre, he can legitimately tell the man that Life itself has a hard time killing Benjamin, and Guaron is weaksauce by comparison.
Causality is causality, no matter "when" it is. If the chain of events are there, then they're there. So "when" doesn't really matter much beyond the contents of said causality itself.
Think of it this way: if you got the power to transplant (or copy) bits of causality from one universe to another, then having that causality occur whenever you wish is practically a non-issue. Especially with the Malleable Causality System to smooth things over.
We're already playing fast and loose with causality. Prime example: I'm going to have it that Benjamin's appendix rupture (which, IRL happened circa 08/2019) occurred prior to his employment with Funthom Industries. Why? So when he faces off against Guaron during the St. Valentine's Eve Massacre, he can legitimately tell the man that Life itself has a hard time killing Benjamin, and Guaron is weaksauce by comparison.
Causality is causality, no matter "when" it is. If the chain of events are there, then they're there. So "when" doesn't really matter much beyond the contents of said causality itself.
Think of it this way: if you got the power to transplant (or copy) bits of causality from one universe to another, then having that causality occur whenever you wish is practically a non-issue. Especially with the Malleable Causality System to smooth things over.