Will parachutes be provided? Republican House leaders informed their rank-and-file on a conference call Thursday that they have to be back at work at 6:30 p.m. Sunday – giving them, oh, 29.5 hours to forestall the “fiscal cliff.”

Absent a last-minute compromise, Americans will see across-the-board income-tax hikes and painful federal spending cuts come into force January 1. Some economists fear that, taken together, the measures could plunge the economy into a new recession.

Technically, however, the Congress could vote the cliff into oblivion at any time – either before OR after the income-tax increases and spending cuts are slated to take effect. Republican House Majority Leader Eric Cantor noted on Twitter that lawmakers “may be in session through Wednesday, January 2.”

House Speaker John Boehner told his troops on the conference call that the Senate would have to act first, either by passing, or by amending, legislation the House has already passed to avert the cliff.

“If the Senate will not approve these bills and send them to the president to be signed into law in their current form, they must be amended and returned to the House,” he said, according to a source on the call.

“Once this has occurred, the House will then consider whether to accept the bills as amended, or to send them back to the Senate with additional amendments,” Boehner said. “The House will take this action on whatever the Senate can pass – but the Senate must act.”

Obama cut short his family Christmas vacation in Hawaii, arriving at the White House on Thursday. But before leaving his native state, the president telephoned Democratic Senate Majority Leader Harry Reid, Boehner, Republican Minority Leader Mitch McConnell, and Democratic House Minority Leader Nancy Pelosi, according to White House Communications Director Dan Pfeiffer.

The news came after Reid delivered a bleak assessment of the cliff talks, essentially predicting that the country would go over the cliff and delivering a harsh personal attack on Boehner.