In some other threads people said that it resets after about 15 minutes when you port out / log off. But this seems not to be always the case. Yesterday I crashed at the last boss, logged back in and was in Wayrest again. Today my bufffood run while trying to kill the last boss, I ported out, got some from my bank and when I ported back in I was at the first stage again even though it took me less than 10 minuts from entering the first to leaving the last loadscreen.