This is where I'm at, after about 25 hours of work. The portrait is a large one for coloured pencil - about 64cm X 52cm - so it takes quite a while to fill in washes.
The colours are a bit warmer than shown here. This photo was taken in fading light, this afternoon, but it's clear, even from this, that more work needs to be done on the hair. The hair looked dark in the reference photo and was lacking enough contrast because of poor lighting. This has meant that I've had to compensate with artistic licence. I think it still needs to be lightened somewhat to reflect the golden tones of the subject's hair.