Speirs’s margin in his seat of Black would drop from 2.8 per cent to 1 per cent under a proposal put forward on Thursday by the Electoral Districts Boundaries Commission, the independent body which redraws South Australia’s electoral map after each state election.

The draft redistricting could cause headaches for the Liberal Party if Speirs – who sensationally resigned the party leadership last week – follows through on his threat to move to the crossbench after Monday’s leadership ballot that saw Vincent Tarzia elected as his successor.

Speirs, who has not publicly endorsed Tarzia’s leadership and is said to be “keeping his options open” about his Liberal Party future, talked with the new Opposition leader for the first time on Thursday – ending a days-long standoff before Speirs flew out to Scotland this morning.

Tarzia described his call with Speirs as a “really productive, positive chat”, adding: “I’m confident he will remain in the Liberal family.”

“It was a positive discussion, of course, it’s a private discussion and I’ll respect that privacy,” Tarzia said in his first press conference since Monday when he won the party leadership.

“I made it very clear that there’s a role for David Speirs in the Liberal Party family.

“I think, as you can acknowledge and appreciate, he’s had a very challenging week, and I think it’s a really good thing that he’s now taking the time to go overseas and go to his cousin’s wedding, and I’m going to be in regular contact with him.”

Tarzia also hinted at changes to the shadow cabinet under his leadership.

“What I can say is that the details of the reshuffle will be finalised in the coming days,” he said.

Tarzia’s pledge to win back government in 2026 was not made any easier by the boundaries commission yesterday, with most of the state’s marginal seats left unchanged while Labor’s position was actually strengthened in the northeastern seat of King.

Under the draft proposal, Speirs’s seat of Black would lose the suburb of South Brighton to the neighbouring seat of Gibson – held by first-term Labor MP Sarah Andrews – but gain Old Reynella from the seat of Reynell, held by Labor Minister Katrine Hildyard.

The newly-proposed electorate of Black, incorporating Old Reynella to the south and losing South Brighton in the north. Image: EDBC

Speirs has represented South Brighton since 2014, and it was his second strongest polling booth at the 2022 state election with 56.9 per cent of the two-party preferred vote going his way.

Conversely, Old Reynella is a strong Labor booth, breaking 65.5 per cent for Hildyard in 2022.

Speirs told InDaily he was “not too concerned” about the proposed changes.

“I’m a boy from the south and I hold the party’s only seat in the southern suburbs, probably a bit against the odds considering results in neighbouring seats,” he said in a statement.

“If I contest the 2026 state election, which is currently my intention, I think I’d be able to resonate with the good folks to Old Reynella in the same way as I gain comfortable majorities in booths like Sheidow Park South and Trott Park.”

File photo: Speirs grabbing a coffee in his electorate in 2022 after announcing his bid to be Liberal Party leader. Photo: Tony Lewis/InDaily

Speirs suffered a 6.5 per cent swing against him Black in 2022, roughly in line with the overall statewide swing to Labor.

The former Environment Minister pointed to his pet projects of creating Glenthorne National Park and opening Happy Valley Reservoir for recreation, adding: “My fellow southern suburbs’ residents know that I fight day in and day out for our communities and I get things done.

“All they want is someone who turns up and delivers for them,” he said.

“It will be up to the party’s administrative wing to make submissions as to whether we support the proposed redistribution, but either way, I’m quite comfortable with Old Reynella coming into the seat, as I would be with South Brighton remaining within the boundaries.”

A Labor Party source said Speirs carries a personal vote and would be difficult to dislodge if he ran again.

“As long as he’s there, Black is difficult,” they said, adding that the seat could be a toss-up without him.

Labor ran Sacred Heart teacher Alex Dighton as its candidate in Black in 2022.

Flinders University academic Josh Sunman, a sessional lecturer in politics, said Black would be a “very strong pick-up opportunity” for Labor if Speirs decided not to run again.

“I think without David Speirs in the seat of Black, the Liberals have a really tough time holding it, even on the old boundaries,” he said, adding that Old Reynella was “heavy Labor territory”.

“If he were to run as an independent… maybe he has the community profile. I know he has a lot of strong support in Hallett Cove and is well known in the community there, but state-level independents don’t have a fantastic record.

“In suburban seats, it’s quite tough for independents to get elected even if they were the sitting member for a major party.”

Labor’s position in Gibson would be slightly weakened if South Brighton was shifted from Speirs’s seat.

The commission projects Sarah Andrews’s margin would shrink 0.2 points to 2.4 per cent, making Gibson Labor’s second most marginal seat behind Dunstan.

Andrews defeated Liberal minister Corey Wingard in 2022 with a huge 12.5 per cent swing.

Labor margin set to increase in King

Meanwhile, Labor looks set to receive an unexpected boost in its northeastern marginal seat of King held by first-term MP Rhiannon Pearce.

The boundaries commission has proposed adding Craigmore to the seat while shifting out Salisbury East, moving the seat closer to Labor’s northern suburbs strongholds rather than east towards Liberal territory in Schubert.

The newly proposed electorate of King incorporating Craigmore and losing Salisbury East. Map: EDBC

The proposed changes would increase Pearce’s margin from 2.7 per cent to 5.7 per cent. Pearce defeated sitting Liberal MP Paula Luethen to win the seat in 2022.

Luethen was, statistically, the Liberal Party’s best performer in a marginal seat at the last election, only suffering a 3.5 per cent swing against her in King – well below the statewide swing to Labor of 6.5 per cent.

One Liberal source said the unfavourable redraw means it is “far less likely” that Luethen will recontest the seat in 2026. Another source said her candidacy was “a big factor”.

A Facebook post from Paula Luethen on Monday.

“It helps and it’s welcome if she’s the candidate,” the source said.

InDaily has contacted Luethen for comment.

The former MP has remained active on social media as a self-described “community advocate” and recently posted an endorsement of the new Liberal leader, touting Tarzia’s “commitment to advancing the interests of people living in the North East suburbs”.

“Here are a few pictures of Vincent listening to how we can improve outcomes and serve people living in King,” Luethen posted on Monday.

The boundaries commission will take another round of written and oral submissions from the political parties and MPs before gazetting its final electoral map in November 2024.