A computer program product, according to one embodiment, includes a computer readable storage medium having program instructions embodied therewith. The computer readable storage medium is not a transitory signal per se. Moreover, the program instructions readable and/or executable by a controller to cause the controller to perform a method which includes: determining, by the controller, whether a difference between information and corresponding design values is in a range; and computing, by the controller and using the information, data describing a lateral writing position to use during writing such that shingled track edges are aligned according to a format in response to determining that the difference between the information and corresponding design values is not in the range. The information corresponds to how an array of writers write and/or are expected to write to a magnetic medium during shingled recording.