You guys keep flaffing about the wrong sources/quotes.
The OP was very clear in his question, so in effect is the HMRC:
The 2011 Autumn Fiscal Event confirmed the decision to extend APD to business jets and other smaller aircraft. These changes will take effect from 1 April 2013, and this guidance will be updated to reflect implementation in due course.
The rates and procedures for aircraft over 5.7t haven't been published yet, so lets get back to the subject on hand once they have.