But an investor who bought the same bond amid the devastation of Hurricane Maria, when nearly everybody else was selling, would have paid around 20 percent of the face value. From his perspective, the new debt plan more than triples his money.

To nudge some disappointed investors into supporting the plan, the oversight board is playing something of a game of chicken with those who bought Puerto Rico’s most recent vintages of general obligation bonds, issued in 2012 and 2014.

The board has said it believes the newer bonds should never have been issued because they took the island over its legal debt limit. The new plan offers investors who hold them settlements well below the 64 cents on the dollar the other bondholders are getting. If they don’t like it, they can sue, and try to convince the federal judge overseeing the case, Laura Taylor Swain, that their bonds are valid. If they win, they would get 64 cents on the dollar like everyone else. If they lose, they would get nothing — and the money set aside for them would be given instead to the investors already getting 64 cents.

Other legal challenges await the plan from bondholders who believe the board was far too generous to Puerto Rico’s retired government workers.

Over the years, the government of Puerto Rico, seeing the huge problem the unfunded pension obligations presented, made some moves to limit the damage. In 2013, it forced new hires into a defined contribution plan, similar to a 401(k). A few years later, it forced all current employees, regardless of hire date, into such a plan.