At current rates, the NHS could offer a coronavirus vaccine to the 32 million people in the first nine priority groups by Easter – four weeks ahead of the official schedule – according to analysis by the Guardian. Government and health sources have described the ambition as to “under-promise and over deliver” amid an expectation that short-term pressures on the supply of Pfizer vaccine in February can be compensated for in March. The initial administering of doses have been running at an average of 2.75m over the past four weeks and if that rate were to be maintained over the next seven weeks the 32-million target would be hit on Easter Sunday, 4 April. That would allow for some second doses to be delivered 12 weeks after a first Pfizer or AstraZeneca jab was given at the beginning of the year – and be well ahead of the 30 April deadline set by the government on Monday night. Completing the first nine groups would mean that some protection against coronavirus had been offered to everybody aged over 50, the clinically extremely vulnerable, those with underlying health conditions, and NHS and care workers. Together they account for 99% of all UK deaths from the pandemic. But the shadow health secretary, Jon Ashworth, said it was now vital the government began to outline its plan for the next steps of the vaccine programme, and called for police officers and teachers to be among those given priority next. “Based on the progress of recent weeks the NHS ought to easily hit its next target in advance. As we move into the next phase ministers need to outline a plan to vaccinate those groups particularly at risk including key workers. We still have to do all we can to reduce spread,” Ashworth said. Over the weekend the UK hit the initial target of offering a first dose vaccination to all 15 million people in the first four priority groups by 15 February, hailed by Boris Johnson as an “unprecedented national achievement”. The latest figures show that total has climbed by 275,000 in the last 24 hours to 15.57 million, with people aged between 65 and 69 and those with underlying health conditions now asked to come forward to get the vaccine. The principal concern is how much Pfizer vaccine is available. Nicola Sturgeon, Scotland’s first minister, warned on Tuesday that the US company had “rephased” its delivery, with supplies squeezed for the next few weeks. Pfizer is scaling up production at its manufacturing plant in Belgium and needs to cut back supply while upgrade works are completed – but Sturgeon said that the company’s overall commitment remained unchanged. A Whitehall source added that Pfizer had told ministers that its “overall projected supply” of vaccines to the UK will remain the same to March despite the contraction. The US company has itself already said it will meet existing production targets over the whole first quarter. Figures from Scotland on Tuesday suggested that vaccination rates would be cut by a third from 47,000 a day to 30,000 a day until the Pfizer squeeze – expected to last a fortnight to the end of the month – is resolved. UK ministers refuse to release any figures for the amount of vaccine available, but AstraZeneca is understood to be providing a little over 2 million doses a week, somewhere around two-thirds or more of the recent supply. A short-term contraction along Scottish lines would mean UK vaccination rates dropping from 3m achieved last week to around 2m, until Pfizer was able to lift supply again to its previously stated target. On Monday, NHS England’s chief executive, Sir Simon Stevens, said he thought that the official target of 30 April could be exceeded if more vaccines were available. “If supply increases then we think we can go faster,” he told a Downing Street briefing. The most number of vaccines that have been delivered in a day is 598,000 on 30 January.