That's likely because the £ has rebounded in value against the $ since this time last year when they last set the prices (from about $1.20-.22 up to about $1.29-.32) as it's now stuck around that level for months I would expect a modest readjustment south on prices after the announcement, nothing major, but a welcome trim.
I agree. Yesterday $1000 converted to pounds + 20% VAT was £945. Today the same sum comes out at £925. The pound has strengthen slightly. Not sure it will make a difference though.