Why is June 7 the absolute last moment to allow the petition to mature?

Choices:
A. Because the two-hour immigration meeting takes place on the 7th
B. Because Congress leaves town for a holiday recess
C. not enough information
D. Because the petition needs 218 signatures
Because the two-hour immigration meeting takes place on the 7th
Two signatures. That's all that's needed to force a wide-ranging House debate — and votes — on border security and the immigration status of 700,000 undocumented young people brought to the U.S. as children.
Since moderate Republicans opposed House leadership two weeks ago with a rare discharge petition to force a so-called "queen of the hill" debate (House rule based on the most votes) on immigration, the measure has steadily accumulated support within their own party. The petition needs 218 signatures to start that debate and — with the assumption that all 193 House Democrats will sign on — Republicans need just two more signatures.
But that effort now goes on hold as Congress leaves town for an 11-day holiday recess, giving all sides breathing room to figure out what comes next. Many of the 23 Republican signers of the petition face tough re-election races in their districts this November.
The debate over Deferred Action for Childhood Arrivals (DACA) recipients has challenged lawmakers since last September, when U.S. President Donald Trump ended the program, calling on Congress to find a permanent legislative solution.
Lawmakers will return to Washington facing an immediate deadline. Representative Jeff Denham, a California Republican who is one of the leaders of the petition effort, told reporters that June 7 would be the absolute last moment to allow the petition to mature before lawmakers run up against a seven-week summer recess.
Denham said talks with House leadership and the House Freedom Caucus, a conservative voting bloc seeking significant security concessions in return for a citizenship path for DACA recipients, have been productive.
"We've had an agreement in principle," Denham said of a deal that would provide a 12-year path to citizenship for DACA recipients, known colloquially as Dreamers. "Now it's trying to put that information on paper. So, assuming we can continue to move forward, that is something we would bring to our conference on the 7th when we have our two-hour immigration meeting, but we're prepared to move the votes if the talks break down."