Therefore, its known narrative elements are not a part of the Doctor Who universe as we, on this Wiki, choose to define it. It may have been the basis for a similar story in another medium, however — and that story may indeed be valid.
In 1994, an article in Doctor Who Magazine #215 mentioned plans for "a chilling CYBERMAN adventure, 'Sword of Orion'". Nicholas Briggs believed that Bill Baggs used that title, from a popular Audio Visual (later adapted by Big Finish), to drum up interest and financial backers. (Baggs would take flyers advertising it to conventions) It later turned into Sentinel, where Cybermen would take over a remote island; this would be later used for Auton 2: Sentinel. The plot would then become about trench warfare on another planet; then it would change again to a clash on Earth, where scientists accidentally attract the Cybermen's attention while investigating alien tech. (REF: Downtime – The Lost Years of Doctor Who)
In The Doctors: 30 Years of Time Travel and Beyond, released in 1995, Cyberwar was slated as an "upcoming release", that teamed-up the Cybermen and the Ice Warriors, with designs used to promote the film, created by Chris Fitzgerald, originating from The Dark Dimension. (DOC: The Doctors: 30 Years of Time Travel and Beyond) Baggs would later say he didn't remember that the Ice Warriors were ever meant to appear and thought it was just that the documentary had the Fitzgerald marquettes (without permission to show them). In contrast, Briggs remembered that the Ice Warriors were indeed part of a fourth version of the plot, with a scene where a woman on a motorbike removes her helmet to reveal an Ice Warrior helmet underneath. (REF: Downtime – The Lost Years of Doctor Who)
At this point, Adrian Rigelsford was involved and promised he could get a computer game company involved with funding: something Briggs told Downtime he believed was a lie. Baggs asked Briggs to model the script like a computer game and so he plotted out a structure based on going to 'levels'. World Leisure Corporation was also briefly involved for funding but pulled out early, with Andy Grant worried the licensing would be too difficult. Indeed, planning had started before Baggs had approached the BBC or the Kit Pedler & Gerry Davis estates, though he claimed to DWM at the time that they'd already given their blessing. (Similarly, WLC were said to still be onboard) In the end, the BBC gave permission at their end but negotiations with the estates fell through. With funding and licensing out, the project was put on hold. By now, Briggs handed the project to Tim Saward who had an idea for Cybermen during the Gordon Riots (admitting years later that this would never have been feasibly on the budget) and heard there would be a trilogy of Cyber-stories, while Baggs was thinking of shifting the plans to be films about the Mandragora Helix. (REF: Downtime – The Lost Years of Doctor Who)
Elements of the trench war version of the script were turned into an audio story, Cyber-Hunt, which introduced a new alien race reminiscent of (but distinct from) the Cybermen: the Cyberons. A few years later, Baggs would achieve the goal of a 'Cyberman' video film by commissioning Lance Parkin to write Cyberon; however, Parkin's plot tried to make the Cyberon less like "Aldi own brand Cybermen" and he publicly said these were not the same creatures as in Cyber-Hunt. (REF: Downtime – The Lost Years of Doctor Who)