Timeline 527 refers to the massive backstory that eventually leads to the creation of Timeline 673.
Timeline 527, in context of Timeline 673 and everything created by JackieFuChan616, refers to all previous canon Bionicle info, fanon info which takes place after that, and Hero Factory info released by the Lego Group until Hero Factory's discontinuation in 2014. From that point on, some new fanon info is added which helps explain JackieFuChan616's outcome of those stories and the creation of Timeline 673.
After Mata Nui's demise, the new population of Spherus Magna grew into a thriving civilization. They used the year of reformation as the first year of their new Common Era (C.E.), all recorded events before this year were referred to as Before Common Era (B.C.E.).
15 years later, first contact was made with an alien civilization, and the population of Spherus Magna helped both civilizations live in absolute harmony. The visitors would come and go from Spherus Magna, but the natives refused to leave their new home. 5 years later, the native population of Spherus Magna vanished without a trace. To honor their memory, the alien civilization declared Spherus Magna a sacred place, where no one would be allowed to travel to. They also adopted the Spherus Magna calender.
As time went on, the firsthand accounts of Spherus Magna became stories. Over time the stories became legends. The legends eventually became myths. Eventually, the myths surrounding Spherus Magna were almost entirely forgotten.
WIthin 4100 years, the civilization had transformed into one centered around mutants and machines. It was at this time that the Hero Factory was founded by Mr. Makuro to combat various amounts of crime infesting the universe.
Main Article: Timeline 673
Within ten years following Invasion from Below, the known Universe has been decimated by an unknown enemy. The Hero Factory did not see the attack coming and was completely wiped out with a single blast during a period when all Heroes were called back to the Factory for an unknown reason. With no one to stop the destroyers, the entire universe was wiped out. Eventually, the outcome of these events was seen by a group of mysterious warriors who sent a the Spirit of a Hero back in time to prevent this crisis. Arriving in the past, the timeline divided and Timeline 673 was created.