I use purple products several times a week
But lately I notice a more yellow tinge to my hair. So do other people.
Is this just what happens after bleaching for a while?
Or is it the combination of a sun and ruddier skin?
Sun will fade toners a lot faster, and sun burnt skin can really bring out the warm tones in hair too. Have you tried making your own purple conditioner yet? Doing it that way, making your own toner with a semi, it will usually last longer than using a premade one, especially if you use a longer lasting dye like Pravana Violet. Even the water/pipes can leave some serious tint to the hair, which a chelating shampoo or treatment will take care of