High-lift colour was invented to replace the use of Bleach for those who didn’t want to bleach their hair, but it’s not interchangeable with Bleach.
A regular permanent hair dye mixed with 30vol developer can lift 2-3 levels or, lighten hair from dark to blonde, but not platinum.
High-lift colour offers only a boost to lightening, equal to one extra level on top of what a regular permanent dye would do.
Even though you can lift your hair up to 4 levels using high-lift colour, you’re limited to only using it on virgin (not chemically altered) hair because like other dyes, it will not lighten already dyed hair.
Colour does not lift colour and if you’ve dyed your hair, you will need to use hair colour remover and bleach to remove those unwanted pigments.
This means that you need to already be a natural blonde to use high-lift colour. If you apply a high-lift to brown hair, you will get orange.