Must be a slow day in DXB..
It will work like this, you get tested on arrival at the HQ, you are in uniform so it satifies the testing regulations as per HR manual but not the drugs/drinks regs as per FOM. If you test positive then you will sit around until your duty time and be tested again, that sample, if still positive will be used to fry you. All this talk of lawyers and duty time is driving me to drink....hic