In the wake of a report that a number of Success Academy charter schools have encouraged parents to withdraw unruly students, Success’ leader said Thursday afternoon that “mistakes are sometimes made.”

The report, published by the New York Times on Thursday, found that Success Academy Fort Greene kept a “Got to Go” list of students it wanted to leave the school. The story described suspensions, threats of 911 calls, and frequent meetings being used to prompt parents to send their children elsewhere.

Moskowitz declined to comment extensively on the story at an unrelated event Thursday, but plans to address it at a press conference Friday afternoon. Whether she characterizes the reported actions as isolated occurrences or defends them could steer the fallout from the story, which was quickly seized on by the network’s critics as evidence that it achieves its striking results partly by counseling out challenging students.

“We represent about a hundred thousand families and mistakes are sometimes made,” Moskowitz said. (The network serves more than 11,000 students.) “I want to talk about a mistake that was made in that particular case and I’m going to answer your questions tomorrow.”

Success Academy is the largest charter school network in the city. Its schools post impressive state test results, and most of its students are black or Hispanic and low-income. Moskowitz, its founder and CEO, has become the standard-bearer for a polarizing “no excuses” model of strict discipline and demanding instruction favored by some of the leading charter school networks.

Rumors and anecdotes have long circulated about charter schools pressuring difficult students to voluntarily transfer out, since expulsions are closely regulated. But critics — including the city schools chancellor — have been hard-pressed to prove those accusations.

By the afternoon, the union-allied Alliance for Quality Education had started a social media campaign highlighting aspects of the story, including pictures of Moskowitz with facts from the story and #GotToGo. Two people from AQE attended the Success event on Thursday, one carrying a large poster showing the Times story.

Moskowitz implied that the “Got to Go” list was a mistake. But a press release said Candido Brown — the principal who oversaw that list — would join Moskowitz and other Success principals at the Friday event, indicating that Moskowitz is likely to stand behind the school leader.

The event could also push Success to explain a longstanding contradiction in the way it describes the role of its schools.

On one hand, Moskowitz has defended the idea that not all students are best served by Success Academy. While the charter schools take all students who get a seat through its lotteries, Moskowitz has said Success’ strict discipline rules, high academic standards for progressing to the next grade, and limited services for students with severe disabilities mean that some parents will eventually see other schools as better options for their children.

But she and her school leaders often deride nearby traditional district schools. In a Wall Street Journal piece earlier this month, for example, Success vice principal Nicholas Simmons detailed an “astounding lack of learning” at Wadleigh Secondary School, while two floors above, he wrote, Success Academy thrived.

“About the only difference is that families at Harlem West won an admissions lottery,” he wrote.