Excise exemption for aviation turbine fuel exports to Bhutan extends nil additional duty to such shipments. Amends the excise exemption framework to treat exports of Aviation Turbine Fuel to Bhutan as exempt from the Special Additional Excise Duty by substituting the prior entry and inserting a new serial entry specifying that Aviation Turbine Fuel cleared for export to Bhutan is chargeable at nil per litre, thereby extending the scope of the exemption to include Bhutanian-bound exports; the amendment takes effect the day after notification.