When your hedge fund has lost almost 90% of its value in just two short years, two words had better appear in your correspondence with investors, if you harbor any hope of their retaining your services: “I’m sorry.”

Pershing Square Capital Management’s William Ackman rushed out a second letter to investors in his Pershing Square IV fund after his first—detailing a terrible January and laying out a planned restructuring of the fund—failed to include the requisite apology.

“In my effort to get last week’s letter out promptly, I neglected to apologize,” Ackman wrote in a letter dated Sunday, a copy of which was obtained by The Wall Street Journal. “I am deeply disappointed by PSIV’s dreadful performance and I apologize profusely for the fund’s results to date.”

Those results have been every bit the “disaster” he described to the Journal on Sunday. The fund—which invests exclusively in the securities of retailer Target Corp.—plummeted more than 40% last month, after losing some 68% last year.

In the new letter, Ackman also changes his tune on redemptions. Where he previously warned that investors would only be allowed to get back 15% of what little is left of their investments, he now offered a chance to get all of the remains of their money back, as well as a fee waiver for those who stick it out.

“Our willingness to offer those investors not currently in the main Pershing Square funds a fee waiver is, of course, of little value if they make no future Pershing Square investment,” he wrote. “To their credit, some of these investors, who are for the most part other hedge funds (that comprised approximately $1.3 billion of the original $2 billion of fund capital), have told me that they previously hedged a substantial portion, or in some cases 100% or more, of their exposure to Target through PSIV. Hopefully, this has helped to mitigate their PSIV losses in the event we are never able to recompense them.”