PHOENIX — The Arizona PTA has withdrawn its backing for Gov. Doug Ducey’s teacher pay-raise plan, saying it isn’t financially sustainable.

Beth Simek, the association’s president, said Wednesday that her own research tells her there is no way Ducey can finance the raises and also restore capital funding for schools without cutting other needed programs. Some of the governor’s budget changes could end up hurting the very children the PTA is working to protect, she said.

The change of heart comes just two days after Simek stood with the Arizona School Boards Association and some other school groups to give their blessing to Ducey’s proposal. One purpose of that news conference was to persuade teachers to vote against a strike.

Now the PTA leader’s public reversal comes even as teachers are voting on whether to walk out, with an announcement of the results by organizers of the #RedForEd movement set for Thursday evening, April 19.

And her message to teachers now?

“If they feel like they cannot afford in their personal financial household to walk out, then they should follow their heart,” Simek said. “If they feel they can afford this, or that it’s something they feel morally strongly about, then they should follow their heart and walk out.”

Simek said she was not given all the relevant information about how Ducey planned to finance his plan when he first asked her to sign on in support. She subsequently gathered as many specifics as she could from various other sources, including other state agencies, she said.

Most crucial, she said, are cuts being made elsewhere in the state budget.

For example, Simek said, Ducey’s plan cuts $2.9 million that had been allocated for skilled nursing services in both the state Medicaid program and the Department of Economic Security. Also gone is $1.8 million aid for “critical access hospitals” and $4 million that the governor had proposed in additional dollars for programs serving the developmentally disabled.

“We can’t support that,” Simek said. “That hurts kids and it hurts families.”

Gubernatorial press aide Daniel Scarpinato said nothing in the plan reduces existing funds. Instead, he said, Ducey is simply deciding not to add money to these programs.

Simek said none of this was disclosed to her when she was asked to support Ducey’s plan.

The PTA’s desertion was only part of the bad news Wednesday for Ducey.

In a separate announcement, Save Our Schools Arizona said it, too, cannot support his proposal, which, through a series of raises, would boost average teacher pay by 19 percent over current levels by the 2020-2021 school year. By the time all elements of Ducey’s proposal would be carried out, the price tag would exceed a billion dollars.

Save Our Schools Arizona originally agreed to withhold judgment when Ducey unveiled the plan last week, awaiting details about funding, said spokeswoman Dawn Penich-Thacker.

“It is now clear the existing proposal is not sustainable or comprehensive as a means of increasing educator pay and reinvesting in Arizona’s classrooms and schools,” she said.

The group, which is fighting state plans to spend more state dollars to send children to private and parochial schools, wants the governor and lawmakers to work with education groups and community interests to “collaborate on better ways to invest in Arizona’s starving public education system,” she said.

Scarpinato said Ducey still has “a strong coalition of education champions” backing the plan, and that the governor intends to work to get it passed by lawmakers.

Among those still on board is the Association of School Business Officials.

“We believe that it is sustainable,” even given the uncertainty of the economy, said Chuck Essigs, the organization’s lobbyist.

“We think it’s important that we get money into the teachers’ hands in a significant amount as soon as possible,” Essigs said. “And this plan does that.”

The proposal also has the backing of the Arizona School Boards Association as well as groups representing school superintendents and rural school districts.

Simek stressed that she is not criticizing Ducey for coming up with a plan.

“I hope he will come forward with something else,” she said. “I don’t want this to be the end of the line. And I certainly would be happy to sit down and listen again and start over with something new.”

She specifically rejected the idea that her organization should offer a counterproposal. “To ask a group of volunteers to come up with a plan to support education funding is a little unrealistic,” she said. “That’s what we have a governor and Legislature for.”

Scarpinato said Ducey “has great respect” for the PTA and its leadership.

“We don’t always agree on every issue,” he said. “But we all agree that Arizona needs to do more for our teachers and our kids.”

Still unclear is whether the #RedForEd organizers, Arizona Educators United and the Arizona Education Association, will call a strike even if a majority of those who vote say they want to walk.

Derek Harris said he and other organizers of the movement have a number in their heads — he won’t divulge details — of how wide a margin of support is needed to start a job action. He said it will have to be more than a simple majority, with support from multiple areas of the state.

Whatever the outcome, the movement will not go away. Organizers already reserved space on the Capitol lawn for rallies on Friday and into next week.