I mean its completely dependant on what you've had before, and for how long, and how many times you've ever dyed it, so its anyones guess how it will come out. But I would still day use the remover first before thinking about bleach.
Sorry I should say stripping hair colour is a different process that involves a different product only used in salons, and its a slow process ( i remember having to strip black in the salon and it took a whole day, sore arms, and a big bill at the end!)