Just to expand on that, if you achieve 30,000 miles on, say, 20 April you will become Silver and your new membership year will be 20 April 2007 to 30 April 2008.

If, for example, you then got 60,000 more miles by December 12, you would become Gold and your new membership year would be 12 December 2007 - 31 December 2008.

Your membership year stays the same if you renew at the same level or drop down one or more levels. It changes when you go up a level.