I've just noticed SL isn't availible on itch.io anymore; any idea why, and - is it going to happen here two?

No words from the devs so far...

Dev here - our publisher Mastertronic went into administration a few weeks ago, and we're in the process of sorting out distribution agreements etc. Long story short - everything should be fine, but we're still sorting out the details! Everything's going well with GOG so don't worry too much :)