WASHINGTON -- Huber David Hernandez got a surprising phone call from a friend a few months ago. Congress is working on immigration reform, she said, and it would benefit both of us.

“It was great news,” said Hernandez, who is from Colombia and arrived in Orlando in May 2012 on a three-month tourist visa and never left, eager “to secure a better future, to achieve what they call the American Dream.”

Then his friend called back. “She told me she had heard that only those who entered through 2011 would be covered. It’s incredible that just because of one year we’re not covered. It lowers your morale.”

A wide-ranging immigration bill being debated in the Senate provides a pathway to citizenship for some 11 million undocumented immigrants but excludes people who arrived in the United States illegally after Dec. 31, 2011.

No one is sure how many people would be affected, but it could surpass 300,000. Other exclusions, including those barring the poor from a path to citizenship, would push the number even higher.

The issue is a window into the complexities facing authors of the most ambitious overhaul of immigration law since 1986, the compromises that led to an 867-page bill and the battles under way to shape its many layers.

Sympathy for late arrivals such as Hernandez, 45, is scarce on Capitol Hill but immigrant advocates and some lawmakers are working to move the cutoff date, saying it undermines the objective of wiping the slate clean by legalizing millions of undocumented residents and fixing a broken immigration system.

Democrats on the Senate Judiciary Committee plan to offer amendments this week that would make the cutoff either when the bill was introduced, April 17, or when (if, really) it is enacted.

The 1986 bill had a cutoff of 1982, but the number of undocumented residents only swelled over the years, the result of many factors including lax border security. The 1986 failures are repeatedly invoked by lawmakers today in demanding increased border efforts. But backers of a more lenient date are using the past as well.

“If the idea is to get the issue off the table, they need to bring the maximum number of people out of the shadows,” said Kevin Appleby, director of migration policy for the U.S. Conference of Catholic Bishops. “You’re spending all this political capital and you might as well solve the problem. Otherwise, you’re planting the seeds for another undocumented population several years down the line.”

Archbishop Thomas Wenski of Miami is seeking a meeting this week in Washington with Sen. Marco Rubio, one of the bill’s authors, to press for a more generous date. Wenski argues that the current proposal will only drive people further into the dark or encourage fraud. The bill requires undocumented residents to prove, through utility bills, bank statements, paychecks and other documents, that they were in the United States before the cutoff.

“We’re trying to increase the pressure,” Appleby said, adding that Rubio’s future political ambitions could be hurt by reform that does not cure the problem for good, as the senator says he wants to do.

(One of Rubio’s priorities is a better visa tracking system to crack down on people like Hernandez, who knew he wouldn’t leave after his three-month travel visa expired. Hernandez said he thought it would be too difficult to come through legal means, which often are expensive and require a wait of a decade or longer.))