The advisory group set up to suggest changes to the GST Act on Wednesday deliberated on how to expand the scope of the composition scheme as well as rationalise the reverse charge mechanism process. This was the first meeting of the advisory group after it was formed earlier this week to suggest changes to the GST laws to make it more simple for taxpayers. Industry sources said the deliberations were on issues like doing away with Section 9(4) of CGST Act which deals with reverse charge mechanism.