Access into Upper Hopwood Burn-Lake Hawea Catchement

Planning to head into the Upper Hopwood Burn to look for a chamois in mid February 2025. Old topo G39 showed at track up the true left bank through the gorge but "Moir's Guide- Otago Southern Alps-2005" said not followable.
It also informed that a later marked route started about 1km before the Hopwood Burn crosses Hunter Valley Station Road and went up 300m above the river/ gorge on true right for the initial 2.5kms had had no maintenance for 20yrs (in 2005) and quite overgrown. It informed allow 4hrs to cover thht section then the 6km to the small bivi in the head basin area (a single bunk) taking about 3hrs using the river margin and gravel.

Be keen to hear from anyone if they have any recent (last 1-2 yrs) knowledge on walking access and times up to hut.

It would be difficult to find any track or route going upstream , easy going downstream.
Good challenge , the good part is once you hit the river bed it is easy.