But a single member could object on the grounds that there isn’t a quorum — in this case, 216 lawmakers — in the chamber. A lawmaker could also demand a roll call vote, something leaders in both parties are urging against but warned might happen in notices sent to members late Thursday.

The confusion started in earnest during a private Democratic Caucus call on Thursday afternoon. Pelosi said the House would vote the next day even if a lawmaker forced a roll call vote.

“If we have a quorum tomorrow, we will take a vote tomorrow,” Pelosi said, according to multiple Democrats on the call. “The American people want certainty. We need to get this bill passed tomorrow.”

“We have to get people off their selfishness,” Pelosi added, speaking about Republican threats to demand a roll call vote instead of letting the House clear the package via a simple voice vote.

But Pelosi’s remarks set off a round of head scratching and panic because all previous guidance that members had been given — including earlier on that very call — was that they would have at least 24 hours’ notice to return to the Capitol.

Pelosi’s decision to move forward with the vote on Friday, no matter what, comes as House leaders on both sides worry that one or more of their members will try to cause a scene, demanding a quorum call or a roll call vote, which would require more lawmakers to return to the Capitol.

But House Republican leadership is particularly concerned about the intentions of Rep. Tom Massie (R-Ky.), who drove from his home state to be in Washington for the vote, and has signaled to leadership that he might call for a recorded tally. The White House is aware of the issue, sources said.

Both House Minority Leader Kevin McCarthy (R-Calif.) and House Minority Whip Steve Scalise (R-La.) have been in contact with Massie, according to a Republican leadership aide — but no one is quite sure where he will land.

The speaker’s declaration that an in-person vote could happen on Friday — instead of Saturday, as expected — caught many members off guard, and sent them scrambling to return to Washington earlier than expected. For some, that meant trying to find flights at a time when national airlines have dramatically reduced their service.

And for many lawmakers, there is deep anxiety about returning to the Capitol, which they see as a hotbed for potentially spreading the virus. Many fear it could spread not only on the floor during votes, but also with hundreds of lawmakers en route to Washington on planes and trains.

Pelosi’s staff reaffirmed the plans on a 6 p.m. call with senior aides, advising that any members who were coming back to D.C. should plan to be there by mid-morning on Friday, according to people familiar with the call.

Initially, just a sliver of the Democratic Caucus was expected to return. But now many members are trying to rush back, afraid of not being recorded if there is a roll call vote. House Majority Whip Jim Clyburn (D-S.C.) sent out a notice on Thursday night, asking to know “as soon as possible” who was willing and able to make it to the Capitol on Friday.