Just seen this on the news , seems like researches around the world are thinking the British approach is the right way to go
"They cautioned that there may be uncertainty about the duration of protection with a single dose, but said that the administration of the second dose a month after the first provided “little added benefit in the short term”.
Given the current vaccine shortage, postponement of the second dose is a matter of national security that, if ignored, will certainly result in thousands of COVID-19–related hospitalizations and deaths this winter in the United States,” the authors warned."
www.reuters.com/article/health-coronavirus-pfizer-idUSL4N2KO194