Hey there!
I just wanted to add my two cents here. I think it depends on the sorority but with mine, once you de-pledge, that's it. It is really sad too because one of the girls in my pledge class couldn't do it this semester and really wanted to next semester but those are national's rules. So, it will probably depends on which sorority you want to go back to. You should probably just ask one of the girls in the sorority and they can tell you the specifics.
Hope this helps!