AIUI, mass production of the Oxford vaccine has _already_ started.
Governments essentially said "If you can demonstrate reasonable efficacy and safety, go ahead and start mass production. If your Phase III trials fail, we'll make you whole and dump the doses in a landfill."
Otherwise, you had to wait the entire Phase III duration before even starting production, whereas now you'll essentially have viable vaccine on Day 0 when the Phase III trail concludes.
I wonder will people comparison shop.
Governments have too much incentive to purchase and distribute all they can get their hands on.