Ark Royal,
Yes, it is possible to empty both the supply fuel tanks with 95 litres remaining in the main - but you'd have to:
1. Have switched off both transfer pumps or had them fail - either produces a caption.
2. Ignored the Amber FUEL warning - this isn't strictly a sensor, just a specific total of fuel remaining in the supply tanks being reached.
3. Ignored both RED FUEL LOW warnings with Audio as each supply tank got down to it's trigger level, Approx 26 Port and 22 Stbd and ignored the STBD engine shutting down.
Not sure what the "Chatter" is about the fences being removed post ser no 250. Aircraft after that Ser no have a total fuel capacity of 710 Ltrs as opposed to the 680 Ltrs on airframes before that serial. The walls, fences, call them what you will, that separate the 3 compartments of the tank are still there.
Jimjim, The supply tanks hold slightly different quantities of fuel which is why they always read approx 4Kgs different. Specifically designed that way to ensure that one engine quits before the other just in case you missed all the other signs as described above.