Off My Mind: Time Travel Rules

So in All-New X-Men they kept on talking like the original X-Men being in the present would change the timeline, but it's always been a very well established rule in the Marvel Universe that any changes to the past only create alternate timelines and don't retroactively alter the present.

*Age of Ultron Spoilers*

Now in Age of Ultron Wolverine was able to go back in time and kill Hank Pym to prevent the creation of Ultron in the present.

So I was wondering why they would change such a fundamental rule in their universe, and then I thought about if there could be any recent events in comics that would have caused it. Eventually I remembered something that happened in New Avengers.

While trying to stop the universes from clasping in on each other this happened.

Now all the Infinity Gems were shattered but the time one just vanished. Now According to Reed Richards the Infinity Gems are a constant tied to the existing to the universe and trying to destroy them would cause the universe to react. I believe that this even is what has changed the flow of time to allow the past to change the present like in AoU.

So the destruction of the Infinity Gems has caused the fundamental laws of time to work in an entirely different manner? So there's only one time stream now and it can be irrevocably altered by time travel?

That does feel like the way Marvel is going now-a-days. The old "alternate reality multiverse" is very old hat at this point.

Well there is still a multiverse. I just think the 616 Universe isn't able to branch out into more timelines anymore. Don't forget that ever universe his it's own set of Infinity Gems so they can still branch out into parallel realities and timelines.

I like the idea that the infinity gems being gone would no longer allow alternative universes but I think their ignoring of their own time travel/multiverse rules has been going on for bit longer than that. They kind of stopped sticking to that rule for the last couple years and started making up their own rules to fit the story. The last run of New Mutants is a good example, it was pretty dumb.

I think also that maybe the rule might still be in affect for AOU though. When Wolverine and Sue Storm went back and killed Pym, the future that they returned to had a wolverine and a Sue Storm in it, meaning that it wasn't their present with an altered past, it was a whole different reality.