Forum:KB:Executor Class lead ship

Does anyone know why the Annihilator was built before the Executor in canon? Since the Executor is the namesake of the class and therefore the ship that should be built and completed first. The Annihilator was revealed to be an Executor-class in the Aftermath books. Kind regards  Darth Tomotron   (talk)  14:14, August 1, 2019 (UTC)