i'm not a colorist, but i will share my daughter's experience.
like me, and my father before me, she is graying early, started at 17. so for her wedding 4 years ago her friend who is a colorist did a 'TEMPORARY' color to cover the gray.
ah, she finally cut it all out last year. (it had oxidized and was orangey.)

my hair was darkest brown/black, and i bit the bullet and went cold turkey to transition. happy i did.
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3a, some 2c & 3b, medium texture, porosity normal, low elasticity
washing/cowashing, conditioning, protein tx: [I] curl junkie products
leave in:cj conditioners and treatments as leave in
styling: cj aloe fix gel, cj pattern pusha, cj honey butta leave in, cj cccc, cj ciab.
sealants - jane carter nourish & shine