I had heard a rumour that the road from Grenoble to Briancon was closed, so I stopped at several tourist information centres along the way to inquire - unsuccessfully as they were (incredibly) all closed until 14. Last chance was in Chambery, so I spent the 50 minutes waiting time having lunch. They knew nothing so I had them call Briancon confirming the main road was closed, but being fairly certain that a small alternative road should be open...