Pretty much. Many years ago (OK, not that many) I worked at Clyde Refinery, and there was a single 6 inch pipe that went across the river to BP's facility in Silverwater.
Ahh ... here's where things get tricky, because one side is certainly not going to tell the other what they do
There could be a few explanations. The fuel samples mentioned in the report say they drew the fuel from the bowser. Now, the fuel in the storage tank at the servo is going to be a mix of different batches of fuel, *potentially* from different sources. (ie: Singapore exports a fair amount of fuel to Australia). But, since the sources were mentioned in the report, then this needs to be accounted for.