The software turned out to permit multiple signups for individuals across multiple platforms — health district websites, social media sites, text messages. Anyone could grab the link and register, regardless of whether they were eligible or not.

That led health districts to close registrations because the clinics quickly filled up and to turn away appointments sought by eligible Virginians because ineligible residents had taken the available slots.

The failure to limit registrations to priority eligibilities was roughly similar in both cases. In either case, people who should have been able to get their COVID vaccines according to the rules were unable to sign up because non-eligible or non-local people had filled up all the available appointments.

Virginia Health Department officials quickly spotted the flaws in the PrepMod system, and issued an ultimatum to the company.

The department also began crafting its own workarounds and emergency patches. If those fixes can be expanded into a workable system all its own, Virginia may abandon PrepMod, just as it abandoned VAMS earlier this year.

And just as fewer than 10% of states were using VAMS as of January, a mere 40% of Virginia health districts are using PrepMod.

Last week, the health department said it was considering dropping PrepMod.