GST rate on services by sub-sub-contractor to sub-contractor pertaining to irrigation, construction

In re Shreeji Earth Movers (GST AAAR Gujarat) a) At what rate of tax the liability should be determined on services provided by appellant (sub-contractors) to the main contractor pertaining to the irrigation, construction and maintenance works to the irrigation department, State of Gujarat? b) Under which head we should classify our services to execute irrigation, construction and maintenance work supplied to the irrigation department, State of Gujarat? c) Whether to charge a tax rate of 12% GST or 18% GST? AAR not agree with the contention of the appellant that they are eligible for the conce...