Supporters and critics of the H-2B nonimmigrant guest worker program engage in a year-to-year political tug-of-war on Capitol Hill. This tug-of-war is often intense over what is known as the returning worker exemption, which allows workers who have legally worked as H-2B employees in the U.S. any of the three previous years to return to work in the U.S. without being counted against the cap of 66,000 H-2B annual visas established by Congress in 1991.

Dozens of industries and the U.S. Chamber of Commerce vigorously defend the need for the guest worker program — especially with today’s decade-low unemployment. Program critics include powerful forces that would love to see H-2B abolished. In broad strokes they claim the program takes jobs away from U.S. workers. The critics include, among others, members of Congress, organized labor and The Southern Poverty Law Center.

As it stands now, the H-2B’s immediate future seems secure, at least for 2017. Less certain is the returning worker exemption. Its future rests in part in the language of the FY17 Homeland Security Appropriations bills, in particular the bill being marked up by the House Appropriations Committee.

Read More: Why H-2B is Like “Groundhog Day”

Unexpectedly (and appropriately given the circumstances), the June 12 killing of 49 people at an Orlando nightclub is giving H-2B a bit more time to push for the returning worker provision.

U.S. Rep. Hal Rogers (R-Ky), chairman of the House Appropriations Committee, cited the tragedy in postponing the House bill affecting the H-2B nonimmigrant guest worker program. The committee had scheduled June 14 to finalize the FY17 Homeland Security Appropriations bill. In the wake of the tragedy, the committee moved the markup to Wednesday, June 22.

The delay gives H-2B supporters, including the H-2B Workforce Coalition, extra time to petition House Appropriation Committee members to support an amendment for the returning worker exemption. Program supporters are urging the business owners relying on these workers to contact their respective House committee members either via social media, email and with phone calls.

The House markup follows the Senate Appropriations Committee, which on May 26 passed its version of the Homeland Security Appropriations bill. The Senate version includes language welcomed by the industry to transfer up to $20 million of funding to augment staffing for H-2B and H-2A (nonimmigrant agricultural guest workers) temporary labor certification processing.

The past two years have seen frustrating delays in processing of H-2B petitions, causing small businesses nightmares as they waited for these seasonal workers to be approved and arrive for work. In some cases, owners were forced to turn away projects or scale back the scope of their services and lay off domestic workers, as a result.

Both versions of the bill will come under debate and scrutiny by lawmakers before they can become law.

To review: Congress, through the H-2B program, authorizes the issuance of a total of 66,000 H-2B visas for foreign seasonal workers to nonagricultural service businesses. In recent years, various industries, citing a shortage of available and willing U.S. workers, have pushed to allow guest workers who have worked within the U.S. the past three years to apply for and also receive work authorizations without being counted against the 66,000 visa cap.

Although the landscape industry is the biggest employer of H-2B visa holders, just a fraction of the total number of landscape and lawn care company owners in the U.S. rely upon the government’s seasonal guest worker program — fewer than 2,000 companies, according to the DOL. The National Association of Landscape Professionals (NALP), on its website, shares data from data-crunching IBISWorld citing more than 474,000 companies in the highly fragmented landscape services industry. IBISWorld, again cited by NALP, says the industry employs more than 969,000 workers — or two workers per company.

What do H-2B workers mean to the landscape industry (the industry as a whole) in terms of dollars-and-cents economic activity? It is difficult to determine that. No such study or survey seems to have ever been done. The great majority of landscape and lawn care companies do not use the H-2B program.

Even so, H-2B remains vitally important to those companies relying on it. They include some of the largest companies in the highly fragmented U.S. landscape services industry.

Will you be attending NALP’s Legislative Day on the Hill on July 12? Let us know in the comments below.