AT&T’s honeymoon with a mountain of debt officially ended today. The operator, which was sitting on $162 billion of debt at the end of its most recent quarter, is being targeted by the activist investor firm Elliott Management for what the firm calls “long-term underperformance” and a “series of strategic setbacks.”

Those strategy misfires, according to a scathing letter issued by the investment firm today, include the failed attempt to acquire T-Mobile US followed by the $67 billion acquisition of DirecTV and its $85 billion Time Warner acquisition.

Elliott Management isn’t just blowing off steam. It owns $3.2 billion of AT&T’s common stock and is pushing for a change in leadership, new board members, an outright freeze on merger-and-acquisition activity, and a thorough review of potential divestitures.

“AT&T must undergo a strategic shift away from acquisition and toward execution,” the firm wrote in the letter. “Even aside from the questionable strategic fit of its M&A, AT&T has spent far too much of the past decade in acquisition mode. Acquisitions require a significant allocation of time and resources — both capital and employee time — that AT&T has been unable to spare.”

AT&T has many valuable but non-core assets that should be sold off, according to the firm. Almost everything should be on the table, including large businesses like DirecTV, its Mexico wireless operations, pieces of its wireline footprint, and smaller assets such as its home security business, regional sports networks, its Latin American pay-TV business, operations in Puerto Rico, and many others, the firm argues.

Responding to the broadside, the conglomerate in a statement said it “will review Elliott Management’s perspectives in the context of the company’s business strategy."

“AT&T’s board and management team firmly believe that the focused and successful execution of our strategy is the best path forward to create long-term value for shareholders,” the company added. “This strategy is driven by the unique portfolio of valuable businesses we’ve assembled across communications networks and media and entertainment, and as Elliott points out, is the foundation for significant value creation."

Elliott said its plan would lead to more than $10 billion in savings, including $5 billion in cuts. The firm didn’t call for the ouster of AT&T CEO Randall Stephenson, but its comments about AT&T’s board failing to rein in what it perceives as mismanagement lead to that conclusion all the same.

The questions about management at AT&T come at an interesting time. The company has made a number of moves in the last few weeks following AT&T Communications CEO John Donovan’s announced retirement. AT&T named Jeff McElfresh as its replacement for Donovan, leading the company’s largest business unit starting next month.

John Stankey, CEO of WarnerMedia, was appointed to president and COO of AT&T, which is a new position at the company. The operator also moved Thaddeus Arroyo out of its business unit and over to AT&T Consumer where he will serve as CEO. Anne Chow has assumed the role of CEO at AT&T Business, and Chris Penrose was promoted to president of Advanced Mobility and Enterprise Solution putting him in charge of the carrier’s efforts in IoT, 5G, edge, and cloud computing.

Elliott didn’t acknowledge the executive shuffling and creation of new roles at AT&T in its letter, but those moves have apparently done little to ally the firm’s concerns.

“Under [Stephenson’s] leadership the company has accumulated valuable assets whose value was not reflected in the stock price. When things like that happen, it's only a matter of time until somebody thinks they can realize these profits,” said Roger Entner, founder and lead analyst at Recon Analytics.

When asked if AT&T now has the right team in place to execute on its strategy, Entner replied: “I think the current team represents the best team that they have available.”

Moreover, AT&T’s financials have become increasingly complex and difficult to ascertain during the last few years, and that’s impacted the company’s ability to win over analysts on Wall Street that crave clean financial statements. AT&T’s mountain of debt is also part of that troubling dynamic.

Although it’s a relative drop in the bucket of AT&T’s $269 billion market valuation, Elliott’s $3.2 billion stake in AT&T is “enough for them to do this rallying cry," Entner said, adding, "the question is now will other investors rally to the Elliott standard or the AT&T corporate standard."

Elliott is known for making similar moves, he explained. The investor has taken large positions, written a fiery public letter, and sometimes gained a board seat at other companies. Oftentimes Elliott’s demands also often mirror changes that were already underway within the business being targeted, and that could be enough for the firm to boost the stock price quickly and declare victory.

It’s been almost three years since AT&T’s stock price jumped above $40 per share. Its current 52-week range is between a low of $26.80 and a high of $38.14. AT&T’s stock hit an 18-month high after Elliott’s letter was released, jumping 5.2%, but those gains were paired down to 2% by the end of trading today.

AT&T ended its most recent quarter with $162 billion in debt. The company said it reduced net debt by $6.8 billion during the last quarter, following an $18 billion reduction in debt during the previous 12 months. It remains on target to reach a net debt reduction of $20 billion by the end of 2019. The company reported a high of $180 billion in debt when its acquisition of Time Warner closed in June 2018.