President Trump signs COVID relief, spending bill averting shutdown. So what happens now?

President Trump’s Sunday night decision to sign the combination COVID relief/government spending plan averts a shutdown tomorrow night. The government was funded through 11:59 p.m. Monday. But Mr. Trump’s signature means the government is now funded through September 30, 2021.

The President railed against the combination package last week – even though the final plan was negotiated by the top four bicameral, bipartisan Congressional leaders and his own point man Treasury Secretary Steve Mnuchin.

The plan passed with 359 votes in the House and 92 votes in the Senate.

President Trump objected to foreign aid provisions which he deemed "pork" in the spending provision of the combination measure – even though the president requested much of that money in his budget request sent to Congress earlier this year. Many Republicans opposed any stimulus checks. But after wrangling, the sides settled on $600 checks. Then last week, the president, who was absent from the negotiations, demanded $2,000 direct payments and refused to sign the legislation into law.

BREAKING NEWS ALERTS: Download the FOX 35 news app for the breaking news as it happens and more

So, House Democrats prepped a bill to provide for $2,000 payment checks. This bill will be on the floor late Monday. At this stage, Fox News is told the House will subject this to a two-thirds vote for passage. Watch to see if Republicans align with the president now – or toe their line.

By handling this bill as a "suspension" measure (a process that speeds the bill to the floor but requires a two-thirds vote for passage), approving the plan isn’t guaranteed. But Fox News is told by a member of the House GOP leadership that the measure should secure two-thirds.

Democrats are essentially daring Republicans to vote no. Hitting the two-thirds threshold is a challenge. But, if the House goes through the usual process for the bill, the measure will just be subject to a simple majority for passage.

Democrats crafted the bill in a way to make the implementation of $2,000 checks contingent on the president signing the combo COVID/government funding plan. So, once the President saw the opportunity for the $2,000 with the House planning a bill, he agreed to sign the plan.

MORE NEWS: White box truck playing audio 'similar' to RV in Nashville explosion shuts down Tennessee highway

If the House passes the bill, it’s onto the Senate.

Sen. Roy Blunt, R-Mo., declared on Christmas Eve that he didn’t think the Senate would have the appetite to tackle $2,000 in direct payments.

Then, the question is whether the Senate can handle such a package. The bill could be subject to one if not two filibusters. One, just to start a debate on the bill. The other, to finish the debate on the bill. Both steps require 60 votes to neutralize a filibuster. And, if the Senate does it by the book, the measure could take several days to process. However, if the Senate has the cooperation of all 100 senators, it can move very fast.

However, one senior GOP source doubted that the Senate could tackle the plan once it comes over from the House. And Trump’s maneuver puts GOPers in a tight spot. Support his plan and flip their position – just because he said so -- or, stand their ground and face the president’s ire.

MORE NEWS: COVID-19 vaccine distribution at Oviedo Mall to begin for those with appointments

Had the President not signed the package, Washington was barreling toward a government shutdown.

It’s now obvious that no one truly knew what the president would sign. Or, had President Trump hornswoggled multiple Congressional leaders, hundreds of Congressional Republicans and key players in his administration into believing he would sign this particular package? Unclear.

In conventional circumstances, had Congress faced a government shutdown threat, the House and Senate would have rushed to prepare another interim spending bill. But that wasn’t in the cards. To Congress, it was this bill or nothing. It was too much of a legislative lift just to advance this plan. And even if there were an emergency bill, no one knew if the president would sign that.

Moreover, there was a holiday scheduling problem.

MORE NEWS: What will the weather be like in the final days of 2020, including New Year's Eve?

The House meets Monday afternoon. The Senate isn’t even meeting until Tuesday. So that meant there would be a shutdown if President Trump declined to sign the existing bill before 11:59:59 pm Monday.

A government shutdown is always bad. But a shutdown now would have marked the second shutdown around the holidays in three years.

A shutdown means federal law enforcement officers, working under COVID conditions don’t get paid. It may also have slowed the rollout of the coronavirus vaccine. Or, those who are charged with helping distribute the vaccine may have been working, sans pay.

A shutdown could have meant furloughs for civilian Pentagon employees. Active duty military personnel are deemed essential, but they probably wouldn’t have gotten paychecks, depending on the length of the shutdown.

MORE NEWS: US reaches grim milestone after COVID-19 cases top 19 million

TSA screeners and air traffic controllers are considered essential, processing holiday, pandemic travel. But they wouldn’t have gotten paid. Would they have been willing to work, gratis, under such circumstances?

Keep in mind that glaring absences by air traffic controllers during the 2018-2019 shutdown started to threaten safety. Their truancy prompted an end to that shutdown.

And for everyone demanding that Congressional pay cease during a government shutdown, you’re out of luck.

MORE NEWS: Fauci claims herd immunity numbers were 'guestimates,' settles on 75-80%

The 27th Amendment to the Constitution is clear:

"No law varying the compensation for the services of the Senators and Representatives shall take effect, until an election of Representatives shall have intervened," reads the amendment.

In other words, lawmakers get paid, no matter what. Shutdown or not. One may argue what "varying" means. Some members may elect to place their pay in escrow or donate their salaries to charitable causes during this period. But they still get "paid." There can’t be any "varying in the compensation" until the midterm election of 2022.

MORE NEWS: Disney World calling back some workers as tourists slowly return

Don’t like it?

Get a vote of three-quarters of all states and two-thirds of both the House and Senate to amend the Constitution.

But President Trump signed the bill. That means there won’t be any question about funding the government until next fall.

And then the decision to sign or not to sign, will be up to President-elect Biden.

Get updates on this story from FOXNews.com.