Board Thread:Questions and Answers/@comment-31777595-20180421163531/@comment-27473528-20180422014435

as far I know re roll is for new account if you don't mind loosing the progress you have made

so they reroll on free 50 gems that the game give you..

the way to do it fast is by deleting sakura.db (I may be wrong) after the intro so you can keep re rolling fast without doing the intro..

but for more detailed one you can ask in reddit..

It's for jailbroken device or android, and I don't have them so never try it