position not quantity
"don't run out of gas"
"give us a rundown of fuel sites"
This is not a fuel problem! Let's get back on track. There could have been 90, 100 or even 150kg in the main tank. Still the same problem.
It was simply in the wrong place.The pilot either thought there was fuel in the supply tank when there wasn't or knew that there wasn't but couldn't do anything about it.