Going from mid dark red - blonde

So the red was dyed? I would do another colour remover just on the dark parts to even them up, don't apply it to your ashy roots.

Yeah sorry - it was - I stopped dying it brown and started red and it ended up quite red.

I thought so. Im going to get another one in the morning.

THEN if its kinda evened out, can I put a no 7 dark golden blonde on it? What colour will it go? I wish I could post a photo!

Is the blonde dye a permanent one?

Yep - just checked and its Lloreal Excellence Creme in 7 Natural Dark Blonde.

I would give L'Oreal a ring tomorrow and ask them what volume the peroxide is in that particular dye. If your hair is too fragile for a bleach bath, it is probably too fragile for a permanent dye.
If you do decide to use it do a strand test first.

That's a point. What would u suggest I use instead to acheive desired colour?

I will give them a call.

Just on a further note though I've been using permanent dyes for years with no problems xx

Damage is cumulative, whether from bleach or box dyes or straightening or whatever. If your hair is already quite damaged from the previous box dyes i would use a demi permanent rather than a permanent, as it has lower vol peroxide. If your hair is very damaged i would avoid anything with peroxide and use a true semi such as those by Adore.
I am assuming your hairdresser advised against he bleach bath because your hair is already quite fragile.

If she advised against a bleach bath I definitely wouldn't use a blonde box dye. It likely has 30 in it for that level, which is a higher vol/more damaging than a bleach bath. I would do another color remover or two to get rid of your dye buildup, then uae a semi over it, or a demi at the strongest

What do you think would be less damaging, a bleach bath using a very low volume peroxide or a Demi box colour?

I think it will depend on the peroxide used in both and the time left on the hair. Box demis are generally 10 or 15 vol, some are 20. (I would use my own 10 vol with it.) You can make a bleach bath as strong or weak as you want and leave it on as long as you want. They are used for different things though, a bleach bath will lighten a shade or two, a demi is deposit-only colour, they aren't supposed to lighten your hair and should only be used in a similar or darker colour to your own hair.