The interesting part of this statement is also mentioned in this article: https://www.nytimes.com/2020/12/30/world/europe/uk-covid-19-...

In a departure from prevailing strategies around the world, the British government also decided to begin giving as many people as possible a first vaccine dose rather than holding back supplies for quick second shots, greatly expanding the number of people who will be inoculated.

That decision put Britain at the vanguard of a far-reaching and uncertain experiment in speeding up vaccinations, one that some scientists say could alleviate the suffering wrought by a pandemic that has been killing hundreds of people each day in Britain and thousands more around the world.