ColourB4

Hi, you can use it straight away. No need to wait. But just make sure you have some nice conditioner for afterwards. And that you wait at least a week before bleaching 🙂

You can use colour removers straight away. No need to wait as they're pretty much not damaging. They dry out a little, but nothing a good conditioner won't sort out.

Thank you both so much. I'd better go and get on with it then!  *1*

I'll ask here since it's about ColourB4 as well:
I currently have black dyed hair with a demi, Wella Colour Charm. I wanna achieve a cool dark brown. Since all fading techniques don't seem to help, I bought abox of ColourB4. Can I use it and right after put my demi on? Or will there be reoxidation? I don't really wanna run around with inbetween hair (it will probably be reddish?)

Demi dyes have peroxide, so you'd have to wait a week.

You could use one of adore brown dyes. You can use those straight away as they dont contain peroxide and i find they last quite a lot longer than demi's. If you dont like it then you can redye later on with the demi.

Ah crap, been hoping I could do it tomorrow, but with Adore I'd need to order and that takes so long :/
But thanks for the answers.