I Know 1 Thing and in postpacific they said "The only fix for that exploit is not announcing server restart" xD. I Think it Works on OFF too, i had DS +16 On BnB c1, I Was SpS xD.
Well, Gm Announces The Restart, (!WTB Enchant Weapon X)
about 1 minute before Server restart u use the scroll, if it succeds u log out immidiately! if u get crystals stay logged in, if u stay logged in your progress wont be saved so u will get rollback!
Rollback may be 1 min but it may be 5 mins, i dont know on what it depends..