In reply to cariva: thanks. Getting the Cervinia guides office number on the net wasn't easy, I ended up calling the Zermatt office and getting it from them!
conditions are OK on the Hornli ridge, but not on the Italian ridge, as I was told. Given the fact that Italian ridge is meant to be shorter (from the hut to the summit), but more demanding technically, I don't think I'd want to try that if it's covered in snow. I've already had to retreat from the Hornli ridge in April 3 years ago, climbing that in snowy conditions was no fun.