CVS on Thursday opened “a limited number of appointments” for COVID-19 vaccines at its Charlottesville store.

The appointments were filled by the afternoon, and no new ones will be made until the chain receives a new supply from the federal government sometime next week, a spokeswoman said.

CVS is receiving doses from the vaccine as part of the Federal Retail Pharmacy Program, which is separate from states’ vaccination efforts. The program guarantees the chain 26,000 doses per week for its Virginia stores through the end of February. CVS is spreading those doses between stores in 34 localities.

Per state regulations, only individuals 65 and older who have previously “expressed intent” to receive the vaccine from their local health districts may receive a vaccine from CVS. (People in the Blue Ridge Health District express intent by filling out this online survey.)

Anyone who fits these criteria may register for open appointments directly on the CVS website. Individuals must attest to being older than 65 and having already registered with their health district in order to make the appointment, though a CVS spokeswoman said the system is essentially an honor one. 

It is unclear what day appointments will open in Charlottesville or other Virginia CVS stores, and the chain will not give residents any warning beforehand. What’s more, the appointments are being filled on a “first-come-first-served” basis, meaning the first few hundred people who happen to be online when the appointments go live will get the spots.

“It’s going to be difficult because we’re not getting a ton of doses right now,” Amy Thibault, a spokeswoman for CVS, said on Monday. “So, those appointments are going to be gone within probably minutes.”

The chain hopes to begin receiving a higher volume of doses beginning in March.