WASHINGTON, D.C. — Migrants are already crossing into the U.S. from Mexico, and there are expectations their numbers will grow when the Title 42 public health order is lifted at 11:59 p.m. EDT on Thursday. Senior administration officials said they are “cautiously optimistic” that when migrants learn there are new penalties for trying to cross the border, there will be a change in behavior. 

“We are clear-eyed about the challenges we are likely to face in the days and weeks ahead, which have the potential to be very difficult. Even after nearly two years of preparation, we expect to see large numbers of encounters at our southern border in the days and weeks after May 11,” said Homeland Security Sec. Alejandro Mayorkas.

“This places an incredible strain on our personnel, our facilities and our communities with whom we partner closely. Our plan will deliver results, but it will take time for those results to be fully realized,” he continued. 

Large numbers of migrants initially turned away under Title 42 tried to cross the border again and again with no consequences. But under a new Biden administration policy, most migrants who enter the U.S. by crossing the border illegally — without making an appointment for an asylum interview or seeking protection in a country they pass through — could be barred from reentry and face criminal prosecution if they cross again. 

Mayorkas also announced a new digital advertising campaign that he said aims to counter the misinformation being spread among transnational organizations about U.S. immigration law.  

“We are making it very clear that our border is not open, that crossing irregularly is against the law and that those who are not eligible for relief will be quickly returned,” he said. “Do not listen to the lies of the smugglers. This is what will happen to you. You will be returned.” 

To further deter migrants from amassing at the border, the administration plans to open 100 processing centers in the Western Hemisphere and increase the number of asylum interview appointments at points of entry to as many as a thousand a day.

The administration previously announced that it would allow a total of 30,000 nationals each month into the U.S. from the four countries where most migrants are from: Cuba, Haiti, Nicaragua and Venezuela. Since January, 100,000 have been accepted in to the U.S.

With Title 42 ending soon, it begs the question — will it be effective?

“I think the answer to that will be determined by the capacity of the administration to process people,” said Muzaffar Chisti, senior fellow from the Migration Policy Institute. “So how many people are returned? And how quickly they're returned? Well, I think it determines the narrative that immigrants will listen to, and that may decide whether they encourage or discourage them from making the journey to the border.” 

Chisti said that while he believes the new rules are more punitive than Title 42, “it takes time for the social media to catch up with that. It takes time for that to permeate down from smugglers to real people.”

He said it will also depend on which countries are being represented among migrants, as well as the effects of any impending litigation. Parts of the administration’s plans are almost certain to face legal challenges from Republican-led states and immigration advocates who fear that these new rules unfairly shut people out of the asylum system.

“Advocates are going to be sharpening their knives in taking the new asylum rule to the courts,” he said. “Those are unknowns, and that will determine whether the strategy unravels or goes into effect.”

House Republicans plan to pass their own border security bill just hours before Title 42 expires that would, in part, bring back some Trump-era policies. 

“My sources in the Mexico area tell me that between Matamoros and Reynosa, we have 50,000 illegal immigrants waiting to cross our border the moment Title 42 is lifted,” said Rep. Monica De La Cruz, R-Edinburg. “The Biden administration has failed the American people. He has failed our border patrol agents. He has failed our border communities.”

Senior administration officials say a lasting solution must include Congress updating the country’s decades old immigration laws.