I think nobody really got to that point... But you can experiment in another way.... Fill-up the tank, now use your scoot normally.... when the light flashes, fill the tank again... then you can compute...
Subtract the amount you just put in from the total tank capacity... the difference is the total amount of fuel/level when the light started to flash... Knowing your fuel consumption, you can now compute how many miles you can go before gas runs out...
In my scoot, when I fill up when the gauge goes to the empty (red) band... I only fill 2 liters... that means I still have 4 liters when the gauge reads empty (tank capacity is 6 liters)... With my fuel consumption of around 50 kms/liter... I can still travel 200 kms. before gas runs out...