Hate to break it to you, but the time to do that was over a year ago, and even then it wasn’t ever really a sure thing - we don’t really know what their backup policies are around that stuff.
This is what the former power user community that made an exodus from Reddit roughly a year ago has been trying to communicate, but a ton of people here seem to enjoy keeping their toes in the water over there, with rather predictable consequences (literally, the post we’re commenting on).
All that said: I am very much looking forward to the absolutely titanic lawsuit around GDPR I’m sure is in the works over this.