It seems to me that for peace of mind one could either:
1) Crank the engine a bit with the kill switch on. This would move some oil from the sump to the tank before you start it.
2) Add a cup (250ml) of oil to the tank to ensure that the pressure pump has enough oil to work with while the scavenge pump starts to move oil to the tank.
The important thing is that the pressure pump has oil to work with when the engine is cold, and once the scavenge system has started to move oil into the tank, there will be no shortage of supply.
Of course, all of this assumes that one didn't simply forget to add oil after an oil change...