Since 2012 there's been a genuine shift. We're accelerating towards a better world. We need as many people as possible to assist by being a "light". Literally just by being a loving and happy person, you are helping the world.
But still nothing wrong with reincarnating in the past. You're free to do so.
I've heard from someone I respect, that reincarnations are not always forward in time, that's not how it works. In fact there's a lot of jumps backwards and forwards.
Just, in whatever time you live, remember to shine that light!
Be the medicine for the world