I went into a vodafone shop and was told it was my phone that was the problem. She claimed it was constantly updating and therefore that was the cause of using 70GB in less than 24 hours.Currently working off two laptops - a Lenovo running windows 10 purely for work purposes, and a clockwork Samsung which refuses to die and still runs XP with no problems (famous last words!) I'll certainly make a note to ask about potential windows 10 issues and report back what they have to say about it.
How she could tell that is beyond me as she never even got past my finger print....lol