The U.S. Census Bureau is ending all counting efforts for the 2020 census on Sept. 30, a month sooner than previously announced, the bureau’s director confirmed Monday in a statement. That includes critical door-knocking efforts and collecting responses onlineover the phone and by mail.

The latest updates to the bureau’s plans are part of efforts to “accelerate the completion of data collection and apportionment counts by our statutory deadline of December 31, 2020, as required by law and directed by the Secretary of Commerce” who oversees the bureau, Director Steven Dillingham said in the written statement posted on the bureau’s website.

These last-minute changes to the constitutionally mandated count of every person living in the U.S. threaten the accuracy of population numbers used to determine the distribution of political representation and federal funding for the next decade.

With roughly 4 out of 10 households nationwide yet to be counted, and already delayed by the coronavirus pandemic, the bureau now has less than two months left to try to reach people of color, immigrants, renters, rural residents and other members of historically undercounted groups who are not likely to fill out a census form on their own.

The bureau’s announcement comes after NPR first reported that the agency had decided to cut short door-knocking efforts for the 2020 census. Those in-person interviews with unresponsive households started last month in some parts of the country and are set to expand nationwide on Aug. 11.

For days, the bureau has been sending mixed signals about its plans by quietly removing references to Oct. 31 — the previously announced end date for all counting efforts — from its website.

Before the pandemic hit, counting for the 2020 census was originally supposed to be finished by the end of July. But in April, with public support from President Trump, the bureau announced that it needed to extend its timeline, including pushing back the end of counting to Oct. 31.

But during a hearing last week before the House Oversight and Reform Committee, Dillingham signaled a shift in plans by telling members of Congress that “the Census Bureau and others really want us to proceed as rapidly as possible.”

The bureau also asked Congress to push back by four months the legal deadline of Dec. 31 for reporting the latest state population counts to the president. Delaying that deadline would allow the bureau to keep counting through Oct. 31 to “ensure the completeness and accuracy of the 2020 Census,” Dillingham and Commerce Secretary Wilbur Ross said in a statement released in April.

Democrats in Congress and many census advocates have become increasingly concerned that the White House is pressuring the bureau to stop counting soon in order to benefit Republicans when House seats are reapportioned and voting districts are redrawn.

As early as May, top career officials at the bureau said the bureau had already “passed the point” of meeting the current census deadlines.

As negotiations over the latest coronavirus relief package continue, there is a window for lawmakers to include a provision that would give the bureau more time.

So far, however, only Democrats have introduced legislation that would extend deadlines, and Republicans have released no similar proposals.