BLACKSBURG -- One day can make a big difference, especially in local government.

Town officials announced this week that they missed a small but crucial deadline, triggering a state law and delaying consideration of an ordinance that would restrict development of Wal-Mart and other large retail stores in Blacksburg.

Opponents of so-called big-box retailers fear the delay will nix any chance the town has to either stop or have more control over Ohio developer Fairmount Properties' plans to build such a store. It would be part of a large commercial development along South Main Street.

The ordinance would limit retail buildings to 80,000 square feet. Larger buildings could be built, but would require another governmental step: approval of a special-use permit.

Economic development advocates fret that, no matter when the vote comes, an approved ordinance could derail attempts to spur the town's flagging retail economy.

Under Virginia law, town council must notify residents at least two weeks before voting on any ordinance. As part of that notification, council is required to run two advertisements in a local newspaper of record. The hitch in this case: The ads must run at least six days apart.

A town employee filling in for someone on vacation bought two ads in The Roanoke Times New River Valley Current section notifying residents that the planning commission would take up the ordinance on May 1, Town Manager Marc Verniel said. The commission was set to take a position on the ordinance and then pass a recommendation to town council, which could have taken its own vote on May 8.

But the ad error prevented that. The first ad ran on April 18. The second should have run on April 25. But the employee, whom Verniel declined to name, inadvertently scheduled the second ad for April 24.

Blacksburg Chief of Planning Brandol Harvey announced the error to the town Planning Commission on Tuesday, minutes before the public hearing was to begin. If passed without proper notification, the ordinance would likely be found invalid if challenged in court, Town Attorney Larry Spencer said later.

So, Spencer said he recommended that action on the ordinance be rescheduled to allow new ads to be run. The earliest council can reschedule a vote would be May 29.

But some open-government advocates and big-box opponents are suspicious of that explanation. In e-mails to officials, resident Mark Lattanzi has questioned the town's interpretation of the state code and written that the explanation for the mistake is "inadequate."

"I hate to think there had been any deliberateness," said Emily Satterwhite, a Southgate Drive resident who opposes a big-box store in the South Main project. But she said she is disappointed that "the vote has been delayed until many residents will be gone for the summer."

Officials, including Vice Mayor Susan Anderson, said this week that they believe the error was unintentional, while acknowledging that suspicion exists.

"We as a council and a staff want to apologize to the residents of Blacksburg for our mistake," said Anderson, a supporter of the ordinance. We ... are probably going to have to work hard to regain some trust ... The perception that something not right happened will still be out there among some people, probably."

Verniel said he is looking into the error and is reviewing the planning and engineering department's public notification processes. "Fortunately staff caught it before the meeting. What would have been worse would be to not to have caught it," Verniel said. "We're going to do whatever we can to make sure it doesn't happen again." He declined to say if any employees would be disciplined for the error.

The Blacksburg Partnership held a meeting Thursday to discuss the ordinance. Partnership President Bill Aden said he is concerned about how the ordinance might affect the group's work. The partnership is the nonprofit economic development arm of the town and is responsible for ongoing retail recruitment. The board of the partnership plans to discuss the ordinance and take a public position on it before May 29, Aden said.

News of the town's error came amid another controversy over The Roanoke Times' ads this week. Twice since October, ads purchased by companies affiliated with developer Jeanne Stosser have been published without attribution. The most recent such ad ran Sunday in support of Fairmount's South Main project. Stosser and business partner Georgia Anne Snyder-Falkinham own the land on which the development is to be built.

Ron Williams oversees advertising sales for the Current. On Wednesday he said the unsigned ad slipped through the newspaper's filters and ran in violation of its standards.

"We just missed it," Williams said.

The newspaper ran a correction on Tuesday naming Llamas LLC, the partnership between Stosser and Snyder-Falkinham, as the sponsor of the ad.

This week the paper instituted new training for ad staff and stricter review processes for handling advocacy ads.

"We owe it to our readers to make sure we don't willingly or knowingly accept ads that are false or misleading," Williams said. But "we're not in partnership with any advertiser to try to circumvent our own rules. We're just not going to do that."