Unveiling the progenitor physics. The trajectory of hybrid bursts in the E_iso − E_p,i plane (Amati relation). Gray squares “Whole” represent the parameters derived from the time-integrated emission (including EE), which mimics collapsars. Blue diamonds (“Main”) represent the initial spike emission, showing a distinct migration back to the merger regime (blue circles) after removing the EE component. The dashed arrows illustrate this physical correction.