After leaders in the Philadelphia suburbs warned this week that it could take three to five months to inoculate everyone in the top-priority 1a group who wants a shot, Pennsylvania officials on Tuesday assured Bucks, Montgomery, Delaware, and Chester Counties that the area “is prime to secure” one of the state’s regional vaccine sites and could see a boost in doses in as soon as two weeks.

Acting Health Secretary Alison Beam said as much in a three-page letter to Southeastern Pennsylvania leaders and lawmakers in which she defended her department against criticism that it has not been transparent with its vaccine-allocation data and that it has not distributed shots equitably to the state’s most populated region.

The suburbs’ regional site will be able to vaccinate “high volumes” of residents soon after the state’s weekly shipments of Johnson & Johnson one-shot doses start arriving around March 28, Beam wrote in the letter released Tuesday evening. She asked the counties’ leaders to “find consensus on a centralized location” with a large capacity to house the clinic, part of a program originally announced Friday.

President Joe Biden did not speak specifically to the suburbs’ frustration with the vaccine rollout while visiting Delaware County on Tuesday to tout his pandemic stimulus package. Last week, Biden said every U.S. adult will be eligible to sign up for a shot on May 1, less than seven weeks away.

Gov. Tom Wolf aims to get Pennsylvanians in 1a vaccinated by then, saying Monday that “we have every reason to believe we’re going to be able to do that,” despite the collar counties’ statements to the contrary.

But since Friday, his administration has not answered questions on whether Southeast Pennsylvanians 65 and older and those with high-risk conditions will have to travel outside their home counties to get vaccinated by May 1.

Beam’s letter provided the state’s most robust response to southeastern officials’ recent complaints but still left questions unanswered. Among them: How many people will be able to be vaccinated at a regional site per week and will it be enough to ensure everyone in 1a who wants a shot can be vaccinated within seven weeks?

At a Tuesday news conference focused on vaccine equity, the state Department of Health provided no details about when exactly the state’s mass clinics will open or what their capacity could be. County officials on Tuesday had a call with Pennsylvania officials regarding the program but said no specifics were provided to them either.

» READ MORE: Philly suburbs can’t inoculate everyone in group 1A by May 1 unless they get a lot more vaccine, officials say

“What we do know is at the county level, especially in the Southeast, people are receiving the vaccine at or above the statewide average,” Department of Health senior adviser Lindsey Mauldin told reporters Tuesday, reiterating the state’s contention that what matters is how many people get vaccinated, regardless of how far they travel. “We are continuing to get more vaccine every week and will continue to work with our county partners, as well as our partners at the Department of Human Services and the Department of the Aging, to ascertain how we can get folks to those appointments.”

Pennsylvania officials have consistently pointed to the vaccine administration rate during tense talks with suburban Philadelphia leaders and lawmakers over the vaccine supply to the counties, where demand for shots is high and appointments are hard to come by. The region has gotten fewer doses per capita than any other section of the commonwealth, according to Inquirer data analyses that the state has said it does not dispute. Local officials say the counties’ vaccine administration rates, which are on par with the state average, do not account for how far residents have had to travel to get those shots.

The state has not indicated how vaccine demand varies by county. But national polls indicate that Republican voters are generally less likely to want the vaccine, and much of Pennsylvania outside the Philadelphia region skews Republican.

» READ MORE: Pa. seniors are ‘at their wit’s ends’ trying to get coronavirus vaccines

The comments of Pennsylvania officials this week marked a continuation of the state’s mixed messaging about vaccine supply in the southeast. Last week, Wolf denied an undersupply, while a Department of Health spokesperson said there had in fact been one but it was unintentional. Aside from future regional sites, the state has not promised any remedies specifically for the region.

Beam in her letter urged the area’s leaders to look at the vaccine rollout as a statewide endeavor, not just one affecting their immediate area, but she did not address whether residents should have to travel to other counties to get vaccinated.

“To be clear, the Commonwealth does not allocate vaccine to a county — we allocate it to providers within a county that deliver care regionally,” she said. “It is inarguable that health care delivery, including obtaining a vaccine, is not restricted to county borders and vaccine allocation is not defined by county lines.”

The acting secretary, who has not appeared at a news conference since March 4, signed an amended order Tuesday giving state vaccine providers until March 31 to schedule every 1a person on their waiting lists, regardless of whether they are already in their patient network, for appointments “as far into the future as necessary.”

She also said in her letter that the state was monitoring vaccine providers to ensure no one opens eligibility to other lower-priority groups until everyone in 1a has appointments. If providers don’t comply, she added, the state will respond by “reducing or turning off their supply of first doses.”

On Monday, Wolf said he did not believe it would take months to get the 1a populations in Montgomery and Chester Counties vaccinated, as officials there have estimated.

By the end of March, “everybody in 1a … will be able to at least say they’ve gotten one vaccine or will have made an appointment in a reasonable period of time, not five months out,” the governor said with a laugh, “a reasonable period of time to get the vaccine.”

» READ MORE: As more vaccine comes, Pa., N.J., and Philly leaders say President Biden’s May 1 goal can be achieved

He noted the state’s share of two-shot Pfizer and Moderna doses is increasing as the federal supply does. However, some suburban counties say their allotment for the next four weeks has increased only slightly, or not at all, and they can only make tentative appointments for the weeks after that since they don’t know those allotments. The governor also pointed to the 200,000 one-shot Johnson & Johnson doses that are set to start flowing into the state each week beginning at the end of the month, and part of which will supply the regional sites.

“It’s helpful to look at the numbers from the full state’s point of view,” Wolf said. “We are getting lots of vaccine. The supply is still not up to demand. But at the rate we’re going, that’s going to change fairly quickly.”