The NBA has announced its return, 85 days after suspending the season because of the coronavirus pandemic.

On Thursday, the NBA's board of governors overwhelmingly approved a proposal for 22 teams to return to play, starting July 31 at the ESPN Wide World of Sports Complex at Walt Disney World Resort in Orlando, Florida.

As players rejoin their teams and prepare to trek to Florida, here is everything known about the plans, everything yet to be resolved and the challenges that must be sorted out.

OK, the NBA has a return-to-play plan in place. What's next?

Before the NBA can come back, teams must reassemble in their home markets. That means bringing back players who left for their hometowns -- or, in some cases, home countries -- while the league sorted out its plans. Players who return from overseas are likely to be subject to a two-week quarantine upon arrival, under current federal rules.

Teams will continue to hold individual workouts in their facilities. A training camp will start June 30 and last a week. All teams will fly to Orlando on July 7, three weeks before the restart of the season. They will likely have to quarantine for some period; Florida law requires people flying in from some states, including New York, to quarantine for 14 days.

There are plans to play some exhibition games, which might end up as scrimmages, among teams before the games begin. That is still in the planning stages.

Have the players signed off on the plan?

The union representatives from all 22 teams will meet Friday to vote on the proposal. Their approval is all but a formality, as NBA commissioner Adam Silver has kept the players involved from the beginning.

Why did the NBA settle on 22 teams?

If the league restarted with only 16 teams, it would have been among the safest and quickest ways to return to basketball and declare a 2020 champion. But those weren't the only factors.

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The total of 22 -- the 16 teams in playoff position plus those within six games of each No. 8 seed -- allows teams to ramp up with regular-season games before the playoffs. The league used the historical context of late-season playoff runs as a guide for how many teams to include. That said, it was a largely invented metric.

The primary reason is money. If the remaining 259 regular-season games had been canceled, the players were facing $645 million in lost salary. Adding 88 games back into the schedule reduces the collective salary loss by $300 million.

Right now, player paychecks are being withheld by 25%. If all remaining regular-season games were canceled, that reduction could've gone to around 40% through November, per front-office insider Bobby Marks. With some of the games added back, that paycheck cut will be reduced significantly. Additionally, it will allow teams to retain some local television revenue that was in danger of being lost.

As an additional benefit, six teams have the chance to play their way into the playoffs over two weeks. ESPN's Kevin Pelton has projections here for the most likely outcomes.

Why did the NBA decide to come back now?

In April, during his last open media availability after a board of governors meeting, Silver laid out the things that would have to happen for the NBA to get back on the court.

"I think we're looking for the number of new [coronavirus] infections to come down," Silver said. "We're looking for the availability of testing on a large scale. We're looking at the path that we're on for potentially a vaccine. We're looking at antivirals. On top of that, we're playing close attention to what the CDC is telling us on a federal level and what these various state rules are that are in place."

In early May, the NBA pivoted on several important points. It reduced its standard for testing on a large scale to making sure there was sufficient testing for front line health workers and symptomatic people. The league also moved away from the idea that it would have to be totally free of the virus to play. Unlike when a single positive test to Rudy Gobert shut down the league, the league began to develop a plan in which it could carry on in the event of a positive test.

In its announcement after the resumption of the season was approved by owners, the league said it and the union have been working with infectious disease specialists, public health experts and government officials to put a plan in place "to prevent and mitigate the risk related to COVID-19." The league is likely to unveil that plan next week.

How long will this take to play out?

Game 7 of the NBA Finals would be no later than Monday, Oct. 12. With the season set to start on July 31, that means the remainder of the season at most would be completed in no more than 74 days.

If there is no need for play-in tournaments to establish the eighth-seeded teams, the start of the playoffs could be moved up several days. The NBA is expected to be aggressive in moving up the dates to start playoff series when the previous round series comes to an end, according to a report by Wojnarowski.

What will the schedule look like?

The regular season will extend 16 days, with five to six games per day. The NBA has branded these "seeding games," and it is likely there will be weekday afternoon playoff games during the first round.

Sources say the league will use three different facilities at first to stage games: The Arena, HP Field House and Visa Athletic Center, all at the Wide World of Sports Complex. As things progress, it will be reduced to two sites and then one. There will be four hours between games on each individual court to accommodate overtimes, cleanings and warm-ups.

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The original 2019-20 regular-season schedule will serve as a guide. Some teams will play games that were previously on their schedule. But there will be a few modifications, as eight teams have been eliminated and the East has only nine teams attending. The NBA is still finalizing some details.

Will there be back-to-backs?

In the eight-game regular-season format, each team is expected to play one back-to-back. The NBA Finals format is expected to include games every other day.

Will these games count toward the regular-season standings?

Yes. In addition to the teams fighting for the eighth seed and a potential play-in tournament, teams firmly in the playoffs will also be jockeying for seeding.

How often will there be testing?

The NBA plans to have daily, uniform coronavirus testing for everyone who is within the bubble, ESPN's Ramona Shelburne reports. Epidemiologists have said this is what the NBA needs to do in order to ensure the safest situation possible for everyone involved. It remains unclear what kind of testing there will be. The players' union has previously indicated it would prefer a testing method other than the nasal swab, which was viewed as invasive and uncomfortable.

There will also be additional layers of protection in place, such as social distancing, temperature checks, use of masks when appropriate, and sanitizing.

What happens if someone tests positive?

After establishing the number of teams, the schedule and its accompanying details, this is the most important issue remaining. The NBA will need to have a comprehensive plan in place to deal with a player, coach or staff member who tests positive.

The league is not expected to stop play because of a positive test. Instead, the NBA will isolate that person and continue to monitor their surrounding colleagues. An outbreak within a team -- if several players or staff members tested positive -- would prove more problematic and could force a reevaluation of the system.

How will the league handle higher-risk individuals?

Among the 22 teams going to Orlando, several have coaches or staff members who are 60 years old or older -- including Gregg Popovich (71), Mike D'Antoni (69), Alvin Gentry (65), Terry Stotts (62) and Rick Carlisle (60). It is expected that they will all take part, but doing so will only add to the concern about the potential for positive tests within the bubble.

What will happen to the eight teams not in attendance?

Teams that are not traveling to Orlando are expected to participate in a minicamp of sorts later this year, in order to avoid a nearly 10-month layoff between game play. What exactly those "OTAs" look like, and whether teams that exit the bubble early will take part, remains unclear.

What happens for players who aren't willing to play?

It is highly unlikely the NBA will force an unwilling player to participate. The league ensured that every team heading to Orlando has an opportunity for a playoff spot. In part, this was done to eliminate any player concerns that the games lacked meaning.

It's unclear, though, what would happen to the salary of a player who declines to play.

How many people from each team will be there?

The NBA is expected to allow 35 people from each team to travel to Orlando.

In reporting about what a potential single-site return-to-play would look like, discussions with coaches and league executives settled on 28 people being the minimum necessary. But with the potential for teams to be on campus for up to three months and having extended practice time, extra personnel will presumably help teams go through training camps and practices, something the league's general managers nearly unanimously favored.

Why will people be able to come and go from the bubble?

The league is expected to house everyone at one hotel and limit access to those outside the bubble. There will be some ability to move around and eat at outdoor restaurants and have some recreation, such as playing golf. But overall, the NBA is expected to keep the bubble tight to prevent the introduction of the coronavirus.

But the league and players' union felt strongly that family members be permitted to join the players. No one wanted the players to be separated from loved ones for potentially such a long duration. There have been discussions about allowing family members to enter the bubble as the season progresses. If that happens, they would be subject to quarantine before entering and tested routinely once inside.

There is the possibility of varying levels of access for some who could travel in and out of the ESPN Wide World of Sports Complex, but the league would restrict direct access to those inside the bubble.

Players who might have to leave the bubble for medical tests (MRIs, etc.) or for personal reasons might be able to return depending on the league's final protocol guidelines.

Will the Orlando Magic have to be in the bubble?

Yes. While the Magic players and staff live within a short distance of Disney World, they will have to enter and remain in the bubble. It might seem silly, but the whole point of an isolated, single site is to maintain an environment that limits exposure to COVID-19.

When will the NBA hold its draft lottery, draft and free agency?

The NBA draft lottery will be on Aug. 25, the draft itself will be Oct. 15 and free agency will begin Oct. 18.

How is the NBA going to handle the draft lottery?

The 14 teams that ultimately don't advance to the playoffs will enter the NBA's draft lottery. The lottery order will be based off the standings as of March 11, when the season was suspended.

So, for example, the Memphis Grizzlies will enter the lottery if they fall out of the eighth seed -- but won't have odds better than 14th. It also means that teams like the Washington Wizards and Phoenix Suns can't improve their draft standing against teams not traveling to Orlando.

When will next season start?

It has been understood for some time that next season's start would be delayed, but that has been codified now that the NBA season could last until Oct. 12 -- within a couple weeks before next season would typically begin.

Next season's training camps could start Nov. 10 with a possible opening night on Dec. 1, sources told ESPN's Adrian Wojnarowski.

And while it is expected there will be a full 82-game regular season, it's still unknown if the season will be played without fans. Not being able to do so will cost the league billions in revenue. Bobby Marks breaks down the financial questions for next season here.

Editor's note: ESPN is owned by The Walt Disney Co.