Moving aside the fact that this fan was in the same room as the Green Arrow himself, Amell revealed during the conference, to the surprise of many, that Arrow was originally designed to run for 5-seasons.
This idea is not all that mind-blowing to discover in current day - considering the foundation of the Arrow series - its flashbacks, lasted for the shows first five seasons, before coming to a full-circle in kicking-off Arrow season 1 during the last minutes of the season 5 finale.
Of course, the season 5 finale of Arrow was one of the best cliffhangers in superhero television to date, and had the crew decided to originally conclude the show as they did the season; the future of the Arrowverse back then would have been entirely different.
While Arrow season 5 ended the infamous series' flashbacks, Arrow season 7 introduced flashforwards - bringing in future versions of Team Arrow members: Felicity Smoak, Dinah Drake, and Rene Ramirez - also bringing in the future versions of Oliver Queen, and Felicity Smoak's children: Willaim Clayton, and Mia Queen, to reshape their idea.
Would you have liked for Arrow to have ended as intended with season 5 serving as the finale to the series?
When presumed-dead billionaire playboy Oliver Queen returns home to Starling City after five years stranded on a remote island in the Pacific, he hides the changes the experience had on him, while secretly seeking reconciliation with his ex, Laurel. By day he picks up where he left off, playing the carefree philanderer he used to be, but at night he dons the alter ego of Arrow and works to right the wrongs of his family and restore the city to its former glory. Complicating his mission is Laurel's father, Detective Quentin Lance, who is determined to put the vigilante behind bars.
Arrow is an American superhero television series developed by Greg Berlanti, Marc Guggenheim, and Andrew Kreisberg based on the DC Comics character Green Arrow, a costumed crime-fighter created by Mort Weisinger and George Papp, and is the first series of the Arrowverse, sharing continuity with other related television series. The series premiered in the United States on The CW on October 10, 2012, and ran for eight seasons until January 28, 2020. Arrow was primarily filmed in Vancouver, British Columbia, Canada