A non-transitory computer readable medium stores an update management program for causing an update on control program, which is installed on each of image processing devices. The update management program, when executed by a processor, causes the computer to: acquire an update program and update function information regarding functions to be updated by the update program from a firmware distribution server; acquire device function information regarding functions of each image processing device from the each image processing device; transmit the update program to the each image processing device; determine an update sequence of timing for causing the each image processing device to update its control program, based on the acquired update function information and the acquired device function information; and cause the each image processing device to update its control program by executing the transmitted update program in accordance with the determined update sequence of timing.