President Joe Biden urged unvaccinated seniors to get their COVID-19 vaccines as quickly as possible on Tuesday, before announcing that all adults across the country should be eligible for shots starting April 19.

“They’re going to have to make the appointment now,” Biden said of seniors during a visit to a vaccination site at Virginia Theological Seminary in Alexandria, Virginia. The visit came ahead of his formal announcement at the White House about eligibility expanding to adults nationwide in less than two weeks.

That does not mean everyone will be able to get vaccines as of April 19, however.

“We’re in a situation where we, I believe, by the end of the summer we’ll have a significant portion of American public vaccinated,” said Biden. “I think before another 25 days we’ll probably have somewhere in excess of 200 million shots that have been administered, and the good news is a clear, overwhelming majority of people over the age of 65 have gotten at least one shot, and that’s the most susceptible age bracket.”

The president’s announcement appears to be in part an effort to end the confusion about which adults are eligible in which jurisdictions. He’s also announcing that 150 million shots have been administered within his first 75 days in office.

In regions that cross state lines, different groups of workers have been eligible based on a hodgepodge of different employment-based criteria. And in some places, retail pharmacies have had different rules from state-run vaccination sites, while county-run sites have had yet another set of regulations.

White House Press Secretary Jen Psaki indicated that the state and local restrictions will be superseded by the president in any laggard jurisdictions once the 19th arrives.

“He is certainly confirming for the public that everyone is eligible around the country. That is a great deal of clarity, they don’t have to go to their local, state website and see when they’re eligible. They know that they are eligible on April 19,” she said Tuesday.

Several large retailers with pharmacies that have participated in the Biden administration’s expansion of the Federal Pharmacy Partnership program did not immediately respond when asked by CQ Roll Call if they would open up to all adults on the president’s directive even in states or localities that do not meet the new timeline.

But that would be a reasonable expectation since Biden previously expanded eligibility to teachers and other school personnel through the program, notwithstanding the protocols being used by various governors.

While simplifying the eligibility rules will streamline the process, expanding eligibility more quickly could also come with tradeoffs. Some experts have cautioned that an earlier eligibility date may not be entirely good news.

Many of the states that have moved up eligibility sooner than the White House’s timeline are lagging behind the national average rate of vaccine distribution. That underscores the challenge of increasing the number of people willing to get the vaccine, and convenient access to the vaccine, especially for people at high risk.

“When we say we’re going to open up eligibility to everybody, to everybody 16 years-old or older, that seems like a victory. In many states that’s an admission of defeat,” said University of Minnesota epidemiologist Michael Osterholm last week. “There is such a pressure to get vaccines administered, needles in the arm, that if you can’t get the people who are really at high risk to come in you just move onto another group to keep those numbers going.”

“Vaccinating people in their homes, finding those who are vaccine hesitant in our communities and reaching out to them, that’s going to take more time. But those are some of the most important people we have to vaccinate,” he said.

But Psaki also said that beyond the effort to provide “clarity,” the administration is highlighting the accomplishment of getting enough supply and personnel to actually deliver the vaccinations and open up eligibility by April 19, earlier than the beginning of May, as Biden has previously suggested.

“That is an accomplishment for the medical field, that’s an accomplishment for the people who are running the operational piece, it’s an accomplishment for the, you know, the the medical experts locally who are running these programs in different states,” Psaki said.

Speaking in Alexandria, Biden also previewed the administration’s effort to provide vaccine supplies to less fortunate countries, once there are assurances of sufficient U.S. stockpiles.

“You can’t build a fence high enough, you can’t build a wall high enough,” the president said. “And we’re only as safe for people who aren’t vaccinated as those folks who have already been vaccinated.”