This dog from reddit appears to be Grownge (greybrownorange) but I suspect that that is not the formal term. What is he really - some kind of dilute?
Not dilute, but liver!
Liver is a modified form of black that turns all black pigment to a brown colour often called liver or chocolate. The dilute gene would turn black pigment to a silver grey that's referred to as blue.
This dog specifically is liver with progressive grey.
This gene is super common in poodles and their mixes. Their colour fades out as they grow into adulthood and sometimes can even turn them silver in places.
In poodles, the colour is called "silver beige". Lots of poodle crosses will use poodle colour terms as well.
Genetics are likely to be: KBKB/bb/D_/E_/Ay_/mm/GG/tt/S_











