A golden bitch who carries chocolate mated to a nice blue roan dog who's parents when a blue roan and tan and a blue roan but has plenty or Tri colours in the back breeding. What probable colours could I expect?

Most likely black and maybe more roans. The stud would have to carry recessive red for a chance to get goldens, and the girl would have to have the tan gene for a chance to get tan points. He would have to also carry choc for a chance to get choc.

So could there be a small chance of chocolate roan

The stud would also have to carry it. If he does each puppy has a 25% chance to be choc. Is there any choc behind him?

If the stud carries recessive red each puppy has a 50/50 chance to be golden. If he doesn't carry recessive red none will be golden

If he carries choc each pup has 25% chance to be choc (on a golden it would be a golden with a brown nose) 75% chance to not be choc.

As he had a patient with tan points he will carry the tan gene at least and will have only 1 dominant black gene. It will depend on if your girl has the dominant black genes and if she has the tan gene when it comes to this.

I believe roan only shows in partly colours, is your girl a solid?

She has a white blaze on her chest but probably be classed as mismarked rather than particoloured the stud has some chocolate in his backbreeding but it's quite far back great grandparents
Thanks Owen

So there is a chance he could carry it carry it then,

Just gave to wait until mother nature takes her course to see if we're expecting