The present invention describes a method of dynamical adjustment for manufacturing a thermally treated steel sheet. The method includes:



A. a control step, wherein at least one sensor detects a deviation happening during the thermal treatment,
B. a calculation step performed when the deviation is detected during the thermal treatment such that a new thermal path TPtarget is determined to reach mtarget taking the deviation into account, such calculation step including:
1) a calculation substep, wherein at least two thermal path, TPx corresponding to one microstructure mx obtained at the end of TPx, are calculated based on TT and the microstructure mi of the steel sheet to reach mtarget,
2) a selection substep wherein one new thermal path TPtarget to reach mtarget is selected, TPtarget being chosen from said TPx and being selected such that mx is the closest to mtarget,
C. a new thermal treatment step, wherein TPtarget is performed online on the steel sheet.