Hi TP,
you are discussing L+R TK LO LVL, this warning occurs with 30 minutes of fuel remaining.
According to the presentation that's an approximate figure. Depending on the aircraft variant and landing weight - our 30 mins reserves are typically about 1 Ton. Many of our fuel flight plans predict landing with about 1500 kgs - hence my original concern at the start of this thread.
Presumably we have to consider an engine failure at the worst point on the intended flight? For our short haul operations - our fuel management problem is a point on the final approach if the crew elect to fly a Go Around.