Among marketplaces where governmental restrictions are keeping practice facilities shuttered, teams are asking the NBA whether players can bypass returns to those cities and report directly to the league's proposed campus environment for the start of training camps, sources told ESPN.

Most teams in regions still adhering to stay-at-home policies amid the coronavirus pandemic have an abundance of players who left their marketplace during the shutdown and would need to quarantine for an extended period -- perhaps as many as 14 days -- prior to joining workouts in team facilities. Teams want to avoid having to quarantine significant portions of their rosters twice --- once upon returning to more restrictive markets, and again, at the bubble site.

In anticipation of the league's expectation of restarting the season, the NBA has told those teams that it plans to work with them on solutions that possibly include redirecting some teams directly to campus/bubble sites instead of team facilities to hold training camps, sources said.

The NBA has a board of governors call set for next Friday, which is expected to provide additional details for teams on a timetable and plan to proceed with the season. Teams are expecting the league to instruct them to start recalling players to their team's markets around June 1, sources told ESPN.

Executives from Brooklyn, Boston, New York and Toronto were among those on Thursday's general manager's call with the league office who expressed concern about how waiting on the league to release a timetable complicates their ramp-ups to return in ways that are unique to those marketplaces, sources said.

For example, here's what Raptors All-Star guard Kyle Lowry wants to avoid: He has been working out in Philadelphia and could have to return to Toronto and quarantine for two weeks -- without a guarantee that Canadian regulations would let him use the team's facility during that period of time. Conditioning gains he had made could be dulled -- just as Lowry and others are looking to accelerate preparation.

Some teams have considered setting up temporary training camps at interim stops prior to arriving at Walt Disney World Resort in Orlando, Florida, where Eastern Conference teams expect they'll be stationed to complete the season, sources said. Twenty-one of the league's practice facilities are open for voluntary workouts but most players on the Knicks and Nets haven't returned to the epicenter of the coronavirus outbreak, New York. In most instances, front-office executives said, they're unable to get players to return to their markets to start preparing for the season's resumption without the commissioner announcing that the season will be resumed.

The standings represent another complication for teams. The Raptors and Nets are firmly in the Eastern Conference playoffs, but the Knicks are waiting to learn whether the NBA will include all 30 teams in the season's resumption -- or keep some teams at the bottom of Eastern and Western Conference standings home for the summer.

In formal and informal conversations with owners, executives and players, the league is still uncertain about the regular season and playoff structure it will use to complete the season.

On Thursday's call, the league was vague in detailing several resumption scenarios still under consideration, including a modified 30-team regular-season schedule directly to the playoffs, pool-play rounds of a play-in tournament and play-in models with fewer than 30, but more than 16 teams, sources said. Several members of the league's board of governors believe that the NBA's preference isn't to bring every team to resume the season, but that remains undecided. First, the fewer teams, the fewer people at risk to spread or contract COVID-19. Also, with little chance to play more than five to seven regular season games, a month of preparation seems like an excessive investment for teams at the bottom of the standings.

And the idea of rewarding the league's very worst teams in a play-in tournament has been met with scant enthusiasm. Among the teams at the bottom of the standings, most privately want nothing more than to keep their draft lottery odds strong -- not dilute those percentages trying to win a handful of meaningless games. They're even less enthusiastic about including key, veteran players and risking injuries in those games.

Nevertheless, 30 teams completing a comparable number of regular-season games prior to the playoffs makes for a more equitable weighting of lottery odds for the NBA draft --- and gives the league a chance to maximize revenue streams for regional sports network television contracts.

Among the concerns of championship contenders in each conference are sitting idly in Orlando or Las Vegas awaiting the results of a play-in tournament, sources said. Contending teams wondered if the NBA would allow them to delay arrivals to the campus site while the play-in tournament is ongoing, "Just so that we don't have to be sitting around waiting on that to end there," one GM told ESPN.

Teams are pressing the league for the timeline, but they're still resisting an official release of it. Among concerns: the uneven process of bringing back players overseas into North America, and some GMs describing voluntary workout environments that are losing momentum and interest among players.

"The novelty of being back in the facility, and how limited it is, has worn off on guys," one GM said. "Our guys are telling the others: Stay away. Keep playing in the high school gym you're using."

The NBA is discussing a step-by-step plan for a resumption of the 2019-2020 season that includes an initial two-week recall of players into team marketplaces for a period of quarantine, one to two weeks of individual workouts at team facilities and a two-to-three week formal training camp, sources told ESPN. Barring an unforeseen turn of events, many NBA owners, executives and NBPA elders believe commissioner Adam Silver will green light the return to play in June -- with games expected to resume sometime before the end of July, sources said.