Thank you all for your assistance. My wife and I went up to Buffalo yesterday and found that conditions were OK but not fantastic. I wasn't able to get there last weekend, so I think we probably missed the best of it.
After reaching the mountain we checked in with the ranger and headed out. From what we could see from the road through cloud there didn't seem to be great opportunities on The Cathedral so we headed on to Cresta.
We parked there and headed up the southern side of The Hump behind the Cresta runs, and found a small chute of reasonably steep firm snow to play on. We didn't head up very high but we could see the rocks towards the summit topped with snow and frost, and the rock we sheltered behind for lunch had a decent coat of verglas.
It struck me that it might be quite an interesting (and challenging) environment for trad climbing on rock in winter, as opposed to alpine climbing on snow/ice. I got a chance to practice building anchors and test out some new gear, and then we departed for home via the cafe at Dingo Dell.
on the way stopped at Absolute Outdoors, a ski hire shop in Porepunkah which sells a bit of climbing gear, for a chat before heading home. Thanks all for your ideas and suggestions.