Amid Donald Trump’s firing of federal agency leaders, one episode has been lost in the flurry of terminations: the ouster of six of seven members of Puerto Rico’s financial oversight board, which has been in charge of the island’s fiscal affairs for nearly a decade. Depending on who he appoints to replace them, the move could send Puerto Rico back to the brink of financial collapse.

In 2016, the island was in the throes of a catastrophic debt crisis. Puerto Rico could no longer pay back tens of billions of dollars it had borrowed — nor could it, as a commonwealth, file for bankruptcy. Fearing that creditor lawsuits would send the island into an economic death spiral, Congress established a bankruptcy process that would help Puerto Rico reduce its debt. The law, known as Promesa, involved the creation of an oversight board — a bipartisan panel of experts to represent Puerto Rico in bankruptcy court and help balance the territory’s budget.

In coordination with the Puerto Rican government — and in the face of a Job-like series of natural disasters including hurricanes, earthquakes and the Covid-19 pandemic — the board, which we have both served on, has made great progress. It has completed the largest public debt restructuring in U.S. history, paring down the government’s debt to some $7.4 billion from around $34 billion. It has shored up Puerto Rico’s depleted public pension system. And it has brought the island’s budget back into the black after years of deficits.

These efforts have prevented the people of Puerto Rico from losing access to basic services such as health care and education, and have given the island a path to a stable financial future.

Now, the board has only one major restructuring left: the Puerto Rico Electric Power Authority, known as Prepa. Decades of mismanagement, damage and neglect have left the utility in woeful shape; grid failures are so common that the rapper Bad Bunny immortalized them in a song. A group of bondholders — including a prominent hedge fund, bond insurers and mutual funds — is demanding full repayment for their claim of about $8.5 billion of principal plus interest, which totals about $12 billion. That could require sharply raising rates for consumers. But Puerto Rico’s electricity rates are already among the highest in the country, and its median household income is just half that of Mississippi, the poorest state in the union. After concluding that full repayment would burden Puerto Ricans and hamper efforts to repair the dilapidated energy system, the board judged that Prepa could repay only a small fraction of the total sum.

For years, this group of bondholders has resisted the board’s efforts to restructure Prepa’s debt, but has largely been locked in a stalemate — until now. The White House, which has not yet replaced the six ousted members, cited the board’s supposed inefficiency as a reason for the purge. But, as figures such as Representative Nydia Velázquez, Democrat of New York, have suggested, it is possible these bondholders have the president’s ear. If that is true, this moment presents a window of opportunity for Mr. Trump to stack the board with creditor-friendly interests. (These bondholders deny that they persuaded the president to intervene on their behalf.)