Cheers Bruce, the one I have is 56.9% abv and my back up is 60.5% so it may well be different malt. The Islay stuff I have a couple of also comes in at different strengths. They all have 8yo on the label.
I'm not sure what the Highland one is but I think it's great stuff, after trying in a few Leith pubs near me, and doesn't need too much water as you say.
When I was trying to source it a friend who works for Ian Macleod pointed me towards Oddbins but I had no joy there, however they (their Glasgow store on Sauchiehall St) suggested it was Macallan as apparently the old 'As we get it' brand (from a Glasgow bottler that IM bought the brand from a few years ago it seems) was always a 'younger cask strength Macallan'.
BTW I sourced it eventually at RMW but stocks vanish fast, particularly the Islay one, and also at getwhisky.com for £19.99
- a great buy so I bought a couple for back-ups!