I'm posting this in behalf of several friends who experienced the game crash on them. When they tried to log back in, they were greeted with the client downloading the patch at around 20%. It was no problem at first since they could download it again but it happened to them a third and second time. They even reinstalled the game and when the game crashed on them again the whole patching at 20% happened again. Three of my friends have experienced this. I wonder if anyone else has had this issue pop-up.

It's quite nasty. I don't want to wait for an hour and a half for the game to re-patch after every crash.

Around 5 or more including me.
I got it once, after that I decided to back up my data in case it happens again. One of those who experienced the same thing replied that replacing the main files with the back up data works rather than re-downloading the game again.