Will hook up DIS tomorrow and see what it says. Don't recall there being a fuel error though when I was diagnosing the pump though.

The suction link between both sides must be working if it empties the opposite, non pump side first. Just very odd that it empties the pump side afterwards.

A chap in on US forum is adamant its the sender on the left side of the tank, i'm not so sure as the gauge is reading correctly at all times.