The technology disclosed herein pertains to a method for determining expected command completion time (CCT), the method including receiving a plurality of position error signals (PESs) for an HDD over a predetermined time period, determining sigma of the plurality of PESs, retrieving upper off-track limits (UOL) for one or more data sectors of the HDD, calculating average number of retrieved sectors (A) between two consecutive occurrences of the |PES|>UOL for the HDD, and determining required number of revolutions (CCT) to collect data based on the average number of retrieved data sectors (A) and a total number of requested data sectors (N).