In reply to Chris Sansum:
Had a great time, thanks Chris,
The sleeper train is great (comfy bed, woken with a bowl of porridge), I've long legs and after being crammed in a National Express bus for over 12 hours years ago, vowed to never go by bus again. Good point with the sleeper is it gets into Aviemore at 07:40 so you've a full day's walking.
Walk thru the Lairig was fairly knackering, light wind / some soft snow but nothing major tho I did go on the east (left) side of the pass and got bogged down by a boulder field, looking back there was a good path on the western side which I eventually joined. Made Corrour Bothy at 4:30 pm so it took 8.5 hours to cover the 13 miles. Was carrying a 50lb pack as I took snowshoes, shovel, crampons, ice axe, tent etc along with some whisky & chocolate bought last minute.
Rained heavily as I camped nr Corrour, had a few inches of snow and strong winds overnight.
Was slow going next day due to the soft snow so decided to try the snow shoes out and they were excellent, really helped. Wore them until the steps down to the Luibeg (which was easy to ford). I didn't use the snowshoes over the Lairig as I had in mind they were only useful for big deep snow fields like I experienced in 2013 but found them great for mixed heather / snow.
Met a couple of groups nr Derry Lodge doing day walks. Was planning to head for Hutchinsons Hut or Fords of Avon bothy depending upon weather / tiredness.
As I headed out of the treeline up Lairig an Laoigh, the wind became stronger and snow deeper so put the snow shoes back on and extra layers. It became a whiteout and had really painful sleet in the face so put a ski mask on. Ended up falling down a few times cause I couldn't gauge the slope and found it very hard going against the wind. Gave up on the Hutchinson hut and decided to continue north to the Avon bothy. Was thinking if the avon outflow was uncrossable then I'll camp nearby and build up a wind break with my snow shovel.
Eventually crossed a medium sized river easily (smaller than Luibeg) and found a hill in front to the north. It was getting dark, I was tired so decided to pull out my emergency gps and saw I was only 600m west from the Fords of Avon bothy and the river I'd crossed was the Avon outflow. Just made the bothy before dark, I see garden sheds in a whole new light now, it's an excellent place and the MBA have done brilliant as it was a horrible mud pit before.
The walk from Corrour to the Bothy took about 8 hours.
Only issue was the door wouldn't shut and after reading Ken from Manchester's comment that it took him 3 hours to get out cause he'd jammed it shut, I left it ajar all night. It looks like it's swollen and needs some wood shaving from the top and lock sides.
Next day, there was deep soft snow all the way up around the side of Bynack so used the snow shoes, found the NE side of Bynack More particularly deep even with the snowshoes and slow going. Weather was excellent though, had sun all day.
Once on the shoulder, ground was firm and took the snow shoes off for the descent. Camped a few hundred metres from the footbridge over the Nethy. Was really hot when I pitched the tent. The walk from Fords of Avon bothy -> Nethy footbridge took 5 hours.
Next day walked to Coylumbridge through the woods, had a pint in Glenmore on the way and camped at Coylumbridge campsite (Rothiemurchus Camping and Caravanning site). Great place, the attendant (Paul) was very backpacking orientated and mentioned a lot of the peoples doing the TGO Challenge stay there in May. Cost £10 which is fair enough and had a few pints in the Woodshed bar around the side of the Hilton Hotel beside the fire. Flew home via Inverness to Gatwick (via train from Aviemore to Inverness, then no. 11 bus to airport).
So the parts of the route I thought would be tough were fine (Lairig Ghru / Fords of Avon crossing) and the Lairig an Laoigh which I hadn't considered as being difficult was the hardest. Had most types of weather from gales, heavy rain, sunshine and snow. That's what I like about the route, it's different every-time. Didn't end up using my ice axe and crampons but would always take them as I may have ended up going higher from Hutchinson to head of Loch Avon, also possibly via Coire Raibeirt.
Hope this helps anyone else considering a similar route.
Rich