Hi,
Liability to the charge is based on whether you have an NPPR property on a particular date each year. For 2010, that date was 31 March 2010. As you will only be renting out the house from July you have no liability for the year. Assuming they keep the same date for next year i.e. 31 March 2011 and your property is still rented you will have a liability for 2011. The payment will be due on or before 30 June 2011.
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