The UK’s main opposition leader Keir Starmer is set to make changes to his top team, selecting the shadow ministers that will lead Labour’s campaign at a general election expected next year.

The changes to the shadow cabinet will be announced on Monday, according to two people familiar with the matter, who asked not to be identified. A spokesperson for the Labour Party declined to comment.

It’s a big moment for Starmer, whose party enjoys a double-digit poll lead over Rishi Sunak’s Conservative Party ahead of a national vote that has to happen by Jan. 2025 at the latest. Given Labour’s polling advantage over the Tories, Starmer’s picks for his shadow ministerial team could reflect the make-up of the next British government.

Starmer “will have thought long and hard” about the changes, Thangam Debbonaire, a member of the current shadow cabinet, told Times Radio on Monday. “He will put together a team that will help fulfill the five missions he’s laid out,” she said, referring to goals focused on the economy, energy, NHS, education, and the justice system.

One of Starmer’s biggest calls relates to his deputy, Angela Rayner, an outspoken figure who is well-liked on the left of the party but with whom Starmer has at times had a tense relationship. The i newspaper reported he may move Rayner to the leveling-up brief, replacing Lisa Nandy, one of the candidates to the party leadership he defeated in 2020.

UK media also suggested Starmer won’t make any changes to posts relating to his core missions, meaning Shadow Chancellor Rachel Reeves, Shadow Home Secretary Yvette Cooper and the holders of the health and education posts, Wes Streeting and Bridget Phillipson may be safe in their jobs.

The Labour changes will coincide with Sue Gray’s first day in post as Starmer’s chief of staff. Gray, who led the investigation into rule-breaking parties in 10 Downing Street and Whitehall during the coronavirus pandemic, had to serve a six-month cooling-off period before being able to take on the role.

Starmer’s reshuffle follows Sunak’s own minor reorganization of his cabinet last week, in which he installed Grant Shapps as the new defense secretary to replace Ben Wallace, and promoted Claire Coutinho to fill Shapps’s old role of energy secretary. The moves were widely seen as Sunak handing roles to loyalists as he too looks ahead to the next election.

(Updates with more details starting in fifth paragraph.)