Hair coloring with Redken Shades EQ, question for William

Dear William,

I was reading your articles and answers to various questions about color. As I understood, you are a great expert about Redken Shades EQ. I would like to ask you for advice on that. I am using the Shades for 6 months now, going to see my colorist every 6-8 weeks or so.
I have middle lenght brown hair, what are very fine.
Lately, I am getting quite a few grey hair.
I used the semi permanent color before and half
of lenght of my hair still have this reddish-auburn
underton on it. I would like to get closer to my natural color, what is medium brown, but cool brown, more ashy. My stylist used on me the Shades tone "cinnamon", but there is still a lot of red in my hair.
What is the best shade to use in order to geet
the dark, cool brown, maybe with gold, but not red present? I have hazel eyes and my skin has some red in it, so dark golden brown (ashy one) is the best color for me.
Thank you in advance for your advice.
Best regards,
Lena