The simplest answer to this question is; It's not made clear

In general terms, the Q appear to be able to move freely in time and space, potentially to any point within the universe, and certainly to travel within their own lifetimes. Q seems to have an awareness of the future actions of his fellow Q (Quinn) and has absolutely no compunction about sharing that knowledge with him in the episode [Death Wish][1];

> **Q :** *In the Continuum, an individual has an obligation to be responsible **to the path his life will follow.***

On the flipside, after the death of Quinn it appears that Q and the rest of the inhabitants of the Q continuum are cast adrift from the knowledge of their future actions. They fight a bloody and destructive civil war between the forces of order (who want Qs to ensure that they remain true to their future actions) and the forces of individualism who seem to want the Q to have the ability to create paradoxes by not doing so. In the grand scheme it's not clear what the outcome of the war is or how it will affect individual Qs

  [1]: http://www.chakoteya.net/Voyager/210.htm