I have very dark hair naturally. Every time I've tried some version of highlights/lighter foils, it goes too warm for my skin tone. I'm unfortunately of an age where greys are popping through with alarming regularity.
I've been getting foils in a dark ashy brown to match my natural tone to hide the greys. Last time I talked to a hairdresser about getting some lighter colour put through, they said that to maintain the ashy colour I need, I'd have to have regular toners done or it will always go too warm for me.
Is this the case? How often would I need to get a toner done to keep a lighter colour ashy? Are there any other solutions to my problem?