In reply to DANNYdjb:
I once spent three hours trapped in the glen because there was so much traffic, nobody could go back or forwards as all the passing spaces were full. It was a logistical nightmare.
Given the conditions i'm going to guess Udlaidh will be busy this weekend. Either go for a very early start and hope you'll get down the glen before everyone else does. Or park as soon as you think you can and bike the rest.