Cyber-invasion (Attack of the Cybermen)

In 1985, 26th century Neomorph Cybermen from Telos infiltrated Earth. This was recorded by ArcHivist Hegelia as a subtle "second invasion". (TV: Attack of the Cybermen, AUDIO: The Early Cybermen)

By one account, the Cybermen were based on Telos in 2507. (PROSE: The Cyber Files)

Legacy
In one state of reality, the Infinity Doctor cited the Cybermen destroying Earth before the human race had reached its full potential as a threat to Established History. (PROSE: The Infinity Doctors)

Behind the scenes

 * Doctor Who: Cybermen states that the Neomorphs of Telos were from around the year 2530, following the failed attempt to destroy Earth in 2526.
 * TARDIS Cam, a feature of the classic Doctor Who website, also dated the event to 2530.
 * In A History of the Universe and the first two editions of aHistory, the event is arbitrarily dated to 2530, as it is set after The Tomb of the Cybermen. The third edition redates it to circa 2495, based on evidence from the Cyberman audio series.