When should the configuration of the aircraft not be changed after a controllability check?

The configuration of the aircraft should not be changed after a controllability check once the check is complete because the results of this check determine the aircraft's current handling characteristics and performance. Altering the configuration after this point could introduce variables that may compromise safety or lead to unexpected behavior, as the aircraft's performance could change based on different configurations, such as flap settings or gear position.

By maintaining the verified configuration, pilots ensure that they operate the aircraft under consistent and known conditions, which is critical for safe flight operations. Other options, while they may represent various phases of flight, do not encapsulate the key principle of ensuring the integrity and stability of the results obtained during the controllability check, which is fundamental for safe handling of the aircraft moving forward.