General colour remover question

The best way i have found to tackle really stubborn black is to do a light bleach bath between colour removers. So just put it on the fully black parts, the idea isn't to bleach the colour out so much as make the hair more receptive to the next colour remover. The next round of remover should then be more effective. I assume this is because the bleach has opened up the cuticle and started degrading the dye molecules.
Are you keeping the colour remover covered and warm? i wave a hairdryer over it if there is stubborn build up.

Yeah she had me stood over her with a hairdryer yesterday. Hmm might be worth waiting till next weekend and ill help her do a bleach bath then see what happens. For the red that she's after she really won't need to go light it's just that with the black on the ends still it's not going to do anything. Thanks for the advice ill talk to her later and see what she wants to do!

Sorry to have to ask another question on top of this but wondering if you can advise best.
We were going to bleach bath her hair tomorrow in the hopes of getting atleast a slight lift since she is only going for a dark red due to work. I saw her today to go get some supplies and her hair has quite clearly re oxidised which is something I know all too well since mine seems to be prone to it and ruins every hair venture lol. When I left her Monday her hair was definitely black at the mids and ends but atleast the top of her hair was a sort of deep reddy orange like id expect from a colour removed black. It's now like a dark brown at the roots and black the rest :/
I'm sure I was told ages ago that bleaching or bleach bathing over hair that has re oxidised may not do anything and may even just go darker. I think my hair dresser told me this so I'm wondering if this is true? I don't want to bleach bath her hair if it's just going to do nothing but at the same time bleach seems to be the only way of lifting her black out.
is there something we can do to prepare the hair better to help? I was going to make her sit I'm coconut oil a few hours prior but I don't know, is there anything else? Or do we need to leave this now?

Anything with peroxide can cause re-oxidation, as can the oxygen in the air as you have found out. If it has already re-oxidised i doubt bleaching will make it any worse.
To prevent re-oxidation you need to rinse all the dye molecules out. So use really hot water, and keep the hair moving. Rinse for longer than recommended. There is a thread on here (you will have to search) about avoiding re-oxidation, it involved blow drying your hair part of the way through the rinsing process, then rinsing again.
You can also test to see if all the dye molecules are out by putting some neat peroxide on a strand. If it darkens you need to rinse more, if it doesn't you are good to go.

Wicked pixie you're like our guardian angel at the minute haha! Ok so maybe we could give it a go then. We have all the stuff so ill leave it up to her. Thank you so much for your help! Yeah I read all those posts a long time ago and I tried the drying my hair mid way with no difference and I've even done the peroxide one which didn't darken.. next time I washed my hair it was black. I just have that hair that does not want to be any other colour than black which sometimes im fine with and then I miss having colour 🙁 the only way to completely sort it out for me I think would be to cut it all off again but I've just spent a year growing a pixie out so not on the cards right now. Thankyou!!