Philadelphia Orchestra music director Yannick Nézet-Séguin will take up his post as music director of the Metropolitan Opera in September, two years earlier than originally planned, the Met announced Thursday in New York City.

Nézet-Séguin will assume full artistic responsibilities for the orchestra, chorus, and music staff at that time, and will begin what the Met called in its announcement a full-time collaboration with general manager Peter Gelb on all other artistic matters.

The change in Nézet-Séguin's start date comes a little more than two months after the Met suspended its four-decade relationship with conductor James Levine after the New York Times published allegations from three men who accused him of sexual misconduct (a fourth then came forward). Levine has denied the allegations.

Concurrent with the announcement of the move-up in Nézet-Séguin's start date, the Met also announced new funding for the position: a $15 million gift from the Neubauer Family Foundation, which is led by Philadelphians Joseph and Jeanette Lerman-Neubauer. The position will be known as the "Jeanette Lerman-Neubauer Music Director."

What does the new start date mean for Philadelphia Orchestra listeners? Will the conductor have less time to rehearse, perform, and manage artistic matters here?

Nothing changes with this announcement, said Jeremy Rothman, orchestra vice president for artistic planning.

"Yannick is committed to us full-time," said Rothman, adding that when the conductor is not in town, he is easily accessible via Skype, email, or text. "He has always made himself available for planning, for fund-raising, media, for being here for our community, and that will continue."

Nézet-Séguin has a contract in Philadelphia that runs through the 2025-26 season and that says he will lead no fewer than 15 weeks of concerts per season, said Rothman.

Rothman said the Philadelphia Orchestra and the Met were continuing to explore ways of working together, such as, in the 2018-19 season, the orchestra's premiere of Nico Muhly's orchestral suite from his opera Marnie. The full opera is to be premiered by the Met in the same season. The orchestra next season will also work with singers from the Met's Lindemann Young Artist Development Program.

Lerman-Neubauer, a member of the Met board's executive committee, said that her relationship with the Met goes back many years, and that she listened to the Met radio broadcasts as a child. She was encouraged to join the board by her husband, former chairman and CEO of Aramark, chair of the Barnes Foundation board, former chairman of the Philadelphia Orchestra board, and one of the major funders of the orchestra's forthcoming tour to Israel. She said that she was impressed with Gelb and the way the Met's HD broadcasts have developed a diversified audience for the company, and that she met Nézet-Séguin through the Philadelphia Orchestra.

Asked whether the motivation for the donation was about giving to the Met music director position or specifically because Nézet-Séguin was in it, Lerman-Neubauer said:

"For sure, Yannick's presence is what sealed the deal. But not just because of the star power. It's because of the relationship we've had with him working in Philadelphia and how he has been able to strengthen Philadelphia, which we care about deeply also."

She praised the collaborations between the orchestra and the Met, adding: "He brings the artists back and forth. The Renaissance happened because of this kind of exchange of ideas, and these are the players who can do that. They've proven it. That's why we're pleased to get involved."

The earlier start date means Nézet-Séguin will add performances at the Met. By "freeing up some guest-conducting weeks" in both 2018–19 and 2019–20, he will now conduct three operas and two Met Orchestra concerts at Carnegie Hall in each of those seasons, instead of the two operas per season originally scheduled, the company said.