Mayor Bill de Blasio announced Friday morning on the Morning Joe that 90% of Department of Education employees have received at least one dose of the COVID-19 vaccine hours before the mandate is set to go into effect.

He said that includes 93% of teachers and 98% of principals.

Unvaccinated staff must submit proof of vaccination before midnight tonight.

Those who don’t, and also weren’t approved for an exemption or leave, will be removed from the payroll starting Oct. 4.

City officials say there is another growing concern that pertains to school safety agents.

Technically, the agents are NYPD employees, but this mandate also applies to them and News 12 was told only about 79% have received the shot.

Teachers and parents told News 12 they're worried about what will happen if those safety agents suddenly can't work, especially following this week's slashing outside Truman High School in the Bronx.

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Gregory Floyd is the head of the School Safety Agents Union. He says he's encouraging everyone he represents to get vaccinated, but points to the fact that in just the last week, there's been a 7% increase in the number of safety agents who have gotten the shot.

Floyd says the city just needs to give the agents more time.

“Maybe we can get the extra 20% if we can continue to engage the employees in education, and I would hope that those who are not vaccinated by Monday would seek appointments with their personal physicians to ask, ‘Is this the right thing for me to do?’ and in most cases, the doctor would say ‘Yes, you better get that vaccination,’” Floyd says.

In response to the petition to the supreme court, the DOE told News 12, “Plaintiffs have no valid claims and have stated no basis for the court's intervention. Courts have spoken. The health department has the authority to implement a mandate that is firmly grounded in science and the expertise of public health officials from across the nation."

So, unless something happens with that lawsuit, DOE employees must get their first dose of the vaccine today or they won't be allowed to work on Monday.

De Blasio says the vaccine deadline is firm for DOE employees and that the city will immediately find a substitute for Monday and place the employee on unpaid leave.

He added that if the employee gets vaccinated over this weekend after the deadline, the employee can call in and possible adjustments could be made.