Not sure what MU you are going to hunt but if its in Norther BC Oct may be a little late only because of the weather. There will probably be snow and freezing temp so mountain climbing would be dangerous.
Glad to say I have hunted Northern BC
Simon Fraser had pretty good judgement on what he found in BC
Best of luck - I'm quite jealous - It will be another year at least before I can start approaching a goat hunt. Do post pictures/stories when you get there.