My hair may be changing colour - help me go grey gracefully

[gettingtherequickly]

So, I had to cancel a hair appointment a few weeks ago, and have only just got round to rebooking. I'm a 6 week regular, so this is the longest I've gone without a touch-up on root regrowth in about 20 years.

I am was mousey brown with cool tones, which I have highlighted for the last 25 years (since mid teens). My current regrowth has a few silver hairs in it, barely noticeable at the moment, but it's clearly just the start.

I don't mind silver grey hair, in fact I'd like to embrace it, but I don't want to have 2 years of growing out my highlights. What should I be asking my hairdresser for in order to fully embrace the grey?