Anas Sarwar's advisers had been wary about my approach to interview their man. You could hardly blame them. I’ve previously been somewhat disobliging and, occasionally, downright rude about Labour’s Scottish leader. This and the fact that I lean towards independence.

Yet, he’s rarely been anything other than gracious and friendly when we’ve bumped into each other. Some other politicians nurse grudges for old slights lasting many years. Maybe Mr Sarwar does too, but he’s never shown it.

Agreeing to this interview perhaps indicates growing self-confidence and maturity in leading Labour in Scotland. He greets me warmly in the party’s campaign headquarters for the Rutherglen and Hamilton West by-election.

A comfortable Labour win here – and it needs to be comfortable – would provide the first tangible evidence of a change in the wind direction of Scottish politics. The SNP’s citadels, for so long considered shatterproof, have begun to look fragile. Even amongst their most implacable activists there’s a sense that independence won’t be happening any time soon.

The crests of waves are unfamiliar vantage points for Scottish Labour politicians, but Mr Sarwar and his confidantes are looking down from one now … and trying not to lose their balance.

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“The coin has flipped. It used to be that the SNP relished elections and Labour feared them. But now it’s the opposite,” he says. “Most people are thinking about their bills, council tax, petrol and food prices and making ends meet, rather than the politics of constitutional division.

“NHS waiting times are one in seven, meaning that about 10,000 people in this constituency alone are on a waiting list. Voters who’ve been SNP supporters for well over a decade are now saying they’ve lost their way; that they’re getting arrogant in power; that they’re deeply divided.

“Many of the things the SNP would have accused Labour of being 16 years ago – that we were complacent; that we were arrogant in power; that we considered ourselves untouchable and had lost touch with local communities – are now being placed at their door.”

He knows too that my own political, cultural and social values are rooted in four generations of family activism in Labour and the trade unions. But that, like thousands of other Labour-supporting families across Scotland, we’d lately been persuaded by the case for independence. Yet Scottish Labour seemed to regard such views as an anathema. “Surely, you’ve had to re-consider these attitudes,” I suggest.

“I think there’s a large chunk of people who would have been hostile to us around 2014/2015 and who would have been strong supporters of independence,” he says. “But they’re now saying openly that while they still like and support the idea of independence and want a referendum at some point in the future, the SNP has lost its way. And that it’s time for a change.”

“Convince me,” I say. “I mean you say that, yet in the last few years ordinary and elected members have been side-lined merely for saying they were relaxed about a second referendum.”

The Herald: Anas Sarwar and Kevin McKennaAnas Sarwar and Kevin McKenna (Image: free)

He indicates a more laid-back attitude on this, which may also offer proof of feeling easier in the leader’s skin. “I think people will have seen that I’m not the type of person who says: ‘I’m always right; everyone else is wrong and that I’ve got all the right ideas’.

“I’ve been really honest with people. I don’t support independence; I don’t support a referendum. But that doesn’t mean you don’t have the right to support independence, or the right to wish a referendum at some point in the future.

“I have an open-arms approach towards people who don’t share our view of the constitution. The Tories say we’re weak on the Union, which is nonsense and the SNP say we’re hostile to people who support independence. I’m not hostile to anyone. You’re the perfect example of that.”

We both laugh: me uneasily.

“I won’t try to persuade you that you’re wrong on independence, but what I will try and persuade you of is that this doesn’t mean there won’t be other chances of change and that Labour can provide good governance for Scotland. I won’t pretend that Labour has not been in a divided, toxic place in the last 10 years, but I don’t think anyone can say I’ve been factional and tribal in my leadership.

“I think people can see that the Labour Party is back on the pitch and that we’re competing to win elections again. And that we can get rid of this rotten, economically illiterate, morally bankrupt Tory Government.”

We discuss the recent U-turn by Keir Starmer on UK Labour’s position on the self-ID aspect of gender reform. Mr Sarwar signals a significant shift in Scottish Labour’s position without actually saying he’d withdraw support for the Scottish Government’s GRR Bill, now undergoing a legal challenge by the UK Government.

He indicates he’d advised Sir Keir on his new thinking. “I’ve been saying to colleagues across the UK ‘learn the lessons from Scotland. Don’t do it this way. Take people with you. Try and find common ground. Try and find sensible places, rather than allowing it to become this entrenched argument that we’ve got to in Scotland’.

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“I still think that removing the indignities in the process of obtaining a GRC is correct. I also believe, though, that we were right to put in our amendments around protecting single-sex spaces based on biological sex and to support amendments around sex offenders and those awaiting trial for sexual offences.”

I point out to him that, ultimately, he still backed GRR.

“The harsh reality is that as soon as the SNP and the Greens realised they had the numbers to pass the bill, they were no longer willing to compromise and to make sensible and reasonable amendments to the legislation.

“We believe there are still flaws in this legislation and those flaws have to be addressed by the Equality and Human Rights Commission in terms of standard guidance, but also around new Scottish Government guidance on what happens in prisons; in schools and in other individual places. This is to ensure there is a clear protection of single-sex spaces based on biological sex.”

At this point, Jackie Baillie joins our discussion. Scottish Labour’s deputy leader had put down some of the amendments to GRR and accused the Scottish Government of playing bad politics.

“I spoke to them at Stage Three about our amendments and about some of the Conservative amendments and indicated they should support them,” she says. “My bottom line is that while there is a need for reform, we also needed to protect women’s single-sex places at the same time.

“Shona Robison [Cabinet Secretary for Social Justice who introduced the bill] hadn’t really had serious dialogue with the UK Government. They might have met in a room but they weren’t hearing each other. She hadn’t had real dialogue with the EHRC. To cap it all, one Special Advisor came to me a couple of weeks later. I said to her: ‘Why didn’t you pass that amendment? Why didn’t you pass all of those amendments? And she said: “Well, we couldn’t let you get everything you wanted’.

"So, it wasn’t about good legislation, they were just playing politics.”

“If we’d passed the amendments, not just those that I’d put down, but that the Tories had put down, and which their own backbenchers had put down, we would be in a better place.”

We discuss the forthcoming publication of Scotland’s drugs deaths numbers. They’re expected to show a slight reduction, but we’re still far away from losing our tag as the drugs deaths capital of Europe. Here too, Sarwar indicates he’s ready to move his party to a more pro-active position.

“Will you be backing the Tories’ Right to Recovery Bill,” I ask him.

The Bill’s heavy-lifting has been done by FAVOR (Faces and Voices of Recovery) and stresses the crucial importance of funding more rehab beds. The Scottish Government has steadfastly refused to back it.

“We support the principles,” he says.

“Yes, but so does everyone,” I reply.

“Well, we haven’t yet seen the detailed proposals on the Douglas Ross bill, but we will work constructively with the Tories to support the right to rehab. We want to get more actual beds implemented.

“Any reduction in addiction deaths is to be welcomed. It’s also important though to acknowledge that there are still far too many avoidable addiction deaths.

“We’ve become transfixed by the idea that devolution has been about chaos and failure, rather than about finding Scottish solutions to Scottish problems. One of the big challenges we have is that big issues get broken down into constitutional bun-fights.

“The harsh reality is that we have exactly the same drug laws as all the other nations in the UK, yet we have three times the number of drugs deaths.

“Unless we confront that fundamental failure, we’re not going to reduce drugs deaths in this country. And that is about rehabilitation beds; funding for drugs and alcohol partnerships and about specific issues around the culture of alcohol and drugs.”

His advisors now materialise. They chivvy us into cars which will take us to the neighbourhoods where this by-election will be won and lost.

Transfers of political power proceed silently. Only its effects are visible. Last week, though, in the housing developments of Rutherglen and Hamilton and High Blantyre you could almost reach out and touch it.