Just to confirm what furball said and tell you of a nearby alternative........
http://www.invershin.com/
I cannot vouch for the quality of the accommodation only having had the odd pint in the pub there, but their bunkhouse is quite new so I would hope it would be ok.
Should you decide to stay at the Invershin Hotel, I would suggest you make your way first to Bonar Bridge and carry on towards Lairg on the A836, keeping the Kyles of Sutherland on your left. You could go up the other side of the Kyles, but the road is not conducive to faster cycling and you would have to carry your bike down a steep flight of stairs as you cross on the railway bridge at Invershin.
Hi Snorri.

No my route from the early post has changed; I have a week to go, and I'l still dithering

I was going to stay with family on the way to North, vearing off to Nailsea nr bristol and Poulton - le - Flyde nr Preston. But now I'm not

I'm heading straight through ... and I may get together with mattfen and discuss completely different route ... via Ireland

- Joke!!
Are you sure about this bit?
"Stirling to Glencoe - via main roads , this would lead me away from Glasgow. I would like to head west to The Isle of Arron - Oban - Glen Nevis - Loch Ness ( staying at SYHA Loch Ness.)"
It would seem odd to go north as far as Stirling then south to Isle of Arran ?? Then through Glencoe and turn south to Oban??
If indeed you plan to go to Stirling, I would suggest heading for Fife then to Perth and on to the cycle route to Inverness, parallel to the A9, on cycle paths and quiet roads, but at no point on the A9.