TORONTO -- Ontario's minister in charge of the autism program vowed Thursday to "stand unapologetically" for changes to funding that will eliminate a waiting list, but that families say will mean less treatment for kids who need it most.

Children, Community and Social Services Minister Lisa MacLeod defended the plan in a string of media interviews as her chief of staff sparred with advocates on Twitter.

Advocates have indicated they'll fight the changes, and noted their protests in 2016 against the then-Liberal government were successful in getting a policy reversed. But MacLeod indicated the Progressive Conservative government's new autism program is here to stay.

"Certainly people are encouraged to speak their mind," she said. "That said, I will continue to stand unapologetically in supporting all 100 per cent of the children that are faced with autism in the province of Ontario."

MacLeod said she has compassion for the parents, as everyone wants the best for their child, but it was "cruel" that only one quarter of kids with autism in Ontario were receiving treatment while the rest were on a wait list.

Under the new program, money will go directly to families instead of regional service providers, which will mean 23,000 kids would no longer be on a wait list for treatment.

The funding is dependent on age, with families receiving a maximum of $140,000 for a child in treatment from the ages of two to 18, but advocates say intensive therapy can cost up to $80,000 per year.

Families will receive up to $20,000 a year until their child turns six. From that time until they are 18 it would be up to $5,000 a year.

Paolo Magrone's four-year-old son has been on the wait list for nearly two years, and he has been paying out of pocket for therapy at a cost of $5,000 a month. He was expecting that at the end of that wait his son's therapy would be fully funded.

The amount he will receive under the new program will cover treatment for a few months per year until his son, who is non-verbal, is six. Then it will cover only one month per year.

"I understand the point of the new reform, making sure everyone is treated as equal, but it's almost like we're all -- pardon my choice of words -- but equally screwed," he said. "Great, we're all suffering together. Thanks."

Magrone is planning to sell his home to continue paying for therapy and move in with his in-laws.

The Ontario Autism Coalition intends to fight the changes. Former president Bruce McIntosh resigned Wednesday from his post as a staffer for MacLeod's parliamentary assistant in response to the new autism plan.

MacLeod's chief of staff Tim Porter wrote on Twitter that it was a "political stunt by a professional protester."

"I spoke with Gbrucemcintosh right after he had been hired to let him know he would not under any circumstances be engaged in work on the autism plan," Porter wrote in another tweet. "Why would he be? He provided input on the failed (Liberal) plan."

MacLeod, when asked if she thought of the coalition as professional protesters, said, "one could take a look at their logo and take a guess." The logo is of a raised fist.

President Laura Kirby-McIntosh noted that the Progressive Conservatives were strong supporters of the coalition when they were protesting the previous government.

"The (Progressive) Conservative party was quite pleased to stand by us when we were fighting the Liberals," she said. "They love using us as props, but the minute you don't fall completely in line, boom. You're under the bus."

The government said the changes were supported by many in the autism community, including the Holland Bloorview Kids Rehabilitation Hospital, the Children's Hospital of Eastern Ontario and parents.

Applied behavioural analysis therapy costs $55 an hour, on average, experts say.

That money often goes to a three-tiered model of supervision, said clinical psychologist Julie Koudrys, with a senior therapist supervising front-line staff, and a behavioural analyst with perhaps a master's degree or someone with a doctoral degree in charge of an overall program.

Intensive therapy addresses all areas of development, such as listening skills, language, social skills, and daily living skills, Koudrys said.

Jeff Moco's son had three years of intensive therapy to build skills including speech, frustration tolerance and toileting, and he's now able to attend school.

"If he didn't do that, the amount of staff that would be required for him to function just in that environment now, it wouldn't be an option," he said.

The government is also doubling the funding for five diagnostic hubs to $5.5 million a year for the next two years to address the diagnosis waiting list of 2,400 children, who currently wait on average for 31 weeks.