How can i go from redhead to blonde?

I started painting my hair red like a year ago, now that I want to go blonde, some stylist say that my hair has to be stripped from it color first and after that I wont be able to handle the bleaching process, because it will be to damaged and it might...

break, but if it's impossible how can movie stars go from red to blonde, black to blonde, brunette to blonde in one appointment when their hair obviously was dyed as well???

I use to worl in a salon and I change my hair all the time. Usually every month I have something new done. I stripped my hair and the colored it again the same day. Just use some good conditioner or hair repair after you finish. If your hair is really long you will need more hair color. Are you having it done at a salon or doing it yourself. Some salons may not do it, but its up to you if you are paying them. Good luck. But I say go for it.