I’ve heard of long leads before, but this is a pretty far-out confirmation.
Yesterday, Symphogear fans flocked to the first day of Symphogear Live 2018 concert events. At the show, it was announced that the fifth season of the Symphogear anime TV series will air in April 2019.
The series made its début in the Winter 2012 broadcast season.
The most recent season, Senki Zesshō Symphogear AXZ, aired in the Summer 2017 broadcast season. Katsumi Ono (Symphogear seasons 2 & 3, Yu-Gi-Oh! Arc-V) directed project at Satelight, wile Elements Garden (BanG Dream!, Bodacious Space Pirates) scored the soundtrack. Akifumi Kaneko and Noriyasu Agematsu were billed as the original creators of the work.
Source: Anime News Network