To optimize the effort involved when converting a gatherer stitcher which transports initially continuously transported brochures step by step into a stitching station and subsequently into an output station, sensors are assigned to machine components affected by geometrical parameters that are relevant to the process when there is a change of job order and to a reference component. The sensors emit signals defining the phase positions of the machine components, and a controller processing the signals coordinates the phase positions with at least one of the parameters in such a way that the brochures arrive in the output station in a center-oriented manner.