Oh sorry ladies I didn't see that I was needed on Tuesday!!!
Livyliv you MUST wait 7 days and 3 washes before colouring after ColourB4 or it will reoxidise. Okay I admit I folded on day 5 and didn't reoxidise but I did a strand test first. If you really can't live with a temporary colour over the top then you need to choose a week where you are bogging around the house not doing much, maybe half term or the summer holidays and get a nice hat for day trips!!! Who cares for a mere 5-7 days...if you can achieve your ultimate colour? It is shit though but its a shame to go through all that only for it to reoxidise.
Geordiemix - you've probably sorted yours by now but I'd probably have chucked a temporary ash or red over the top just to see what it did if I wanted to keep the highlights, or just coloured over them if I felt it was too much trouble and wasn't really working anyway.
For future reference, if you want to do your own highlights at home I can't recommend enough the Scott Cornwall "foil effects" cap. Its the only way to do home highlights in my opinion.
It comes with a very good booklet that explains it all. What you do is you buy this and you buy some 40 volume peroxide and some bleach powder (Jerome Russell brand, boots or superdrug, fine). You also buy a semi permenant or permenant colour that you want your highlights to be - and you can really look at the colour on the front of the box here because you will be pre-lightening so you don't have to take your original colour into consideration. So if you have chocolate brown hair and you want golden brown highlights, you migth buy Nice n Easy Light Golden Brown. You put the cap on, pull the stuff through, bleach it up to canary yellow, rinse it off WITH THE CAP STILL ON, dry it off, apply your semi/permenant colour, leave that on for the development time, rinse that off WITH THE CAP STILL ON, dry it off to ensure it is the colour you want, then you can take the cap off and I would then recommend washing all your hair to properly get rid of any residue. Its called true toning, and it means that the guess work of how long to leave bleach on to achieve the right "tone" to your highlights is no longer an issue. Its okay for hairdressers - if they get it wrong they can tone your hair at the sink when they rinse you off. But we can't, until this product was invented.
Its all explained in his book which comes with the kit which goes into great detail and I think every home colourist should read it whether they plan on doing highlights or not because it gives a lot of information about home colouring and what the numbers mean and what you can or can't achieve.
Love Scott Cornwall products. Also, he has a facebook page so if you want to ask him a question, you can post it there and he answers in person!!!