A start time to begin transitioning resources to states indicated in the second resource state set is scheduled based upon an estimated amount of processing time to complete transitioning the resources. At a scheduled start time, a process starts in which the states of one or more resources are switched from states indicated by the first resource state set to states indicated by the second resource state set. Scheduling the process of transitioning resource states to begin at a time that allows the process to be completed just in time for the resource states to be immediately available to the processor upon entering the second application state helps minimize adverse effects of resource latency. This calculation for the time that the process should be completed just in time may be enhanced when system states and transitions between states are measured accurately and stored in memory of the portable computing device.