Hi pepper,
I would recommend giving the admissions people in the Council a call. They are very helpful, and will be able to tell you exactly where you would have got into from your specific address last year, which at least gives you an idea of what you might get this year. Also, they ought to be able to make a suggestion re: proof of address, if you're running into difficulties on the form. The number provided in this year's booklet is 020 8871 7316.
The vast majority of the schools in Wandsworth are at least good, so I really wouldn't be dragged into the whirl of panic
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You ought to be able to get into High View on St John's Hill?
All the best with your application!