Hi Glyn, I love the premise for this story. A lot of the writing is very good too -- the character depictions in particular. I agree with everyone's comments -- the story on the page isn't quite delivering the premise. It feels like a somewhat different novel from the one offered. Julie picked up YA and I wondered that too. I don't know enough about SF but I felt there should be a stronger hint that this is also an SF story.
Here are my quick thoughts. I started reading this as a murder mystery, which might have been the wrong approach. In my mind a murder mystery requires a more cut-to-the chase approach on the opening couple of pages. I don't think that means you need the murder very early on but at the moment, as Slago says, the pace isn't pacey. I didn't feel any real sense of threat.
I think there's too much background info on Saffy's character. You indicate very well in a few words that Saffy has a strong personality with firm convictions. I'm confident you have the skills to draw these out as the story progresses. I didn't need so much up front. At the moment the story is getting lost in detail that could come in later chapters.
So, for example:
"Saffy throws her pen at the wall. Its lid is on, so it doesn’t mark any of the clippings and printouts covering the wide pinboard. [Lovely scene setting.] She tightens her fists, and words squeeze out between clenched teeth. ‘I can’t take any more of this!’ [Great start.]
Joe looks up from his laptop. ‘Aw babe,’ he says. ‘Any more of what?’
‘Do not call me babe.’" [Very good characterisation, even if she's not really cross with Joe.]
PERHAPS cut here and go straight to "The photos show small groups of demonstrators sitting on the steps of energy company HQs, on garage forecourts, outside government offices, holding placards with slogans like “Re-think, Re-set”, “No Going Back,” and “Last time covid, next time fire”. One of the demonstrators is Joe, whose placard is more literary: “Not with a bang, not with a whimper, not at all. [I'm guessing this is what the story is about, its theme,, regardless of genre and plot?]
"There’s one of her, too, sitting in ripped black skinnies, her lopsided half-shaved hairstyle falling over one eye. She won’t give up the Lisbet Salander look even though her friends are now in flares. She wears a black t-shirt with a white slogan: “If you don’t agree with me, you don’t yet understand what I’m saying”, the words getting ever smaller down the front. Her own placard follows the same pattern: “If not now, when? If not here, where? If not us, who?” Saffy knew it was too many words when she wrote it out, but she feels responsibility strongly." STOP HERE? and restart with "‘Even the mad professor agrees on the need for a reset,’ Joe adds. [Neat intro of 'mad professor' and emphasise of reset idea.]
I could be wrong of course -- it's your novel! And I'm a menace for cutting other people's prose. But maybe a little bit of deleting...?
Third person, present tense: I like it, and as you say it's flexible. Slago has a good point - some of the writing is distant. Saffy is your main character, at least in this section. Let us get inside her head a bit more:
"There’s one of her, too, sitting in ripped black skinnies,
her lopsided half-shaved hairstyle falling over one eye. She won’t give up the Lisbet Salander look even though her friends are everyone else is now in flares. She wears Her favourite black t-shirt with a white slogan: “If you don’t agree with me, you don’t yet understand what I’m saying”, the words getting ever smaller down the front. Her own The placard following the same pattern: “If not now, when? If not here, where? If not us, who?” Saffy She knew it was too many words when she wrote it, but she feels responsibility strongly every single word had been too important. You couldn't just avoid stuff for convenience."
I hope this helps. As I say, they're instant reactions. I could be off track. I do like the premise though. Very compelling.