In reply to berna:
Hi Berna
I've only climbed the Mittellegi in summer conditions and looking at the webcam below, it is unsuprisingly pretty snowy and icy up there as we are well into October so would be quite a bit harder than it's usual Difficile grade I would wager!
https://www.webcam-4insiders.com/en/weather-Grindelwald/1244-Grindelwald-we...
Also obviously the Mittellegi hut will be long since shut but I'm pretty sure there was a small winter/bivouac shelter about 20 metres down from the main hut, which incidentally is in the most amazing exposed situation and can be seen including the normal approach from the Eismeer Station on the following:
http://www.youtube.com/watch?v=kwAy1T-BP4Q&list=UUkVKguHnrqXx5lAmviy2U8...
Anyway good luck and enjoy the wallet crunching (about £120 for a return ticket 2 years ago) train ride on the Jungfrau express!
Cheers
Dave