When any TV show goes on for long enough, it’s inevitable that there will be a certain amount of inconsistencies cropping up, but Doctor Who, having been around one way or another for roughly 60 years, has more than its fair share. For instance, the lingering issue of the Dalek homeworld Skaro being referenced as existing despite having been previously destroyed has never exactly been cleared up, but at least it’s now been addressed.
The four-part 1988 story “Remembrance of the Daleks” featured the Daleks searching for the Hand of Omega, a ‘stellar manipulator’ used by the Time Lords to burn up stars to fuel time travel. After being acquired by Davros, the Daleks’ creator, he intended to use it as a superweapon to wipe out the Time Lords, but in a culmination of a plan by the Doctor, it instead caused Skaro’s sun to go supernova, incinerating the planet in the process.
The planet’s apparent reforming was brought up in recent publication Dalek Mark III Travel Machine: Combat Training Manual, which states that: “Study of the timeline of Skaro indicates several temporal anomalies relating to its destruction and subsequent reconstruction that are currently being investigated.” While it doesn’t actually explain how the planet came to be reformed, it at least acknowledges its continued existence as a continuity problem.
The issue has actually been addressed previously in 1997 novel War of the Daleks, which stated that a duplicate planet named Antalin had been destroyed in Skaro’s place to address the latter being referenced as still existing in the 1996 TV movie, although the less said about anything in relation to that particular outing the better.
To be fair, writers have played fast and loose with Doctor Who’s continuity for years, which is inevitable since the show’s plots often involve the appearance of temporal anomalies caused by time travel, but one as large as the destruction of the home planet of the Doctor’s archenemy isn’t one that can really be ignored.