Shag Nasty.
You are correct for the tax year April 2010 to March 2011. For 2011 to 2012 the HKIRD assessors are saying that, in the light of the DTA between UK and HK we are now liable for full HK tax. In fact they are saying that we should not be paying UK tax as HK are the pre-eminent authority. This has been stated by an assessor in a face to face meeting.