A method of operating a memory system comprising: a memory controller tracking a time remaining before a scheduled time for performing a high priority, high latency operation to a first memory rank of the memory system, wherein the memory system comprises a plurality of ranks (225,226,227,228) that are individually accessible by different memory access operations scheduled from a command re-order queue of the memory controller; responsive to the time remaining reaching a pre-established early notification time before the schedule time for performing the high priority, high latency operation, biasing the re-order queue containing memory access operations targeting the plurality of ranks (225,226,227,228) to prioritize scheduling of any first memory access operations that target the first memory rank; scheduling the first memory access operations to the first memory rank for early completion relative to other memory access operations in the re-order queue that target other memory ranks (226,227,228); and performing the high priority, high latency operation at the first memory rank at the scheduled time; wherein the biasing of the re-order queue and scheduling of the first memory access operations triggers a faster depletion of first memory access commands remaining within the re-order queue before the high priority, high latency operation is performed at the first memory rank, wherein the high priority, high latency operation is a high priority memory refresh operation and the memory access operations are read commands, and the method comprises: determining a count of deferred memory refresh operations for the first memory rank; responsive to the count approaching a high priority threshold, issuing an early high priority refresh notification for the first memory rank, wherein the high priority threshold indicates the scheduled time for performing a memory refresh operation as a high priority memory refresh operation at the first memory rank; responsive to the early high priority refresh notification, modifying a read reorder queue to give priority scheduling to at least one read command targeting the first memory rank; and executing one or more of the at least one read command on the first memory rank according to the priority scheduling. a memory controller tracking a time remaining before a scheduled time for performing a high priority, high latency operation to a first memory rank of the memory system, wherein the memory system comprises a plurality of ranks (225,226,227,228) that are individually accessible by different memory access operations scheduled from a command re-order queue of the memory controller; responsive to the time remaining reaching a pre-established early notification time before the schedule time for performing the high priority, high latency operation, biasing the re-order queue containing memory access operations targeting the plurality of ranks (225,226,227,228) to prioritize scheduling of any first memory access operations that target the first memory rank; scheduling the first memory access operations to the first memory rank for early completion relative to other memory access operations in the re-order queue that target other memory ranks (226,227,228); and performing the high priority, high latency operation at the first memory rank at the scheduled time; wherein the biasing of the re-order queue and scheduling of the first memory access operations triggers a faster depletion of first memory access commands remaining within the re-order queue before the high priority, high latency operation is performed at the first memory rank, wherein the high priority, high latency operation is a high priority memory refresh operation and the memory access operations are read commands, and the method comprises: determining a count of deferred memory refresh operations for the first memory rank; responsive to the count approaching a high priority threshold, issuing an early high priority refresh notification for the first memory rank, wherein the high priority threshold indicates the scheduled time for performing a memory refresh operation as a high priority memory refresh operation at the first memory rank; responsive to the early high priority refresh notification, modifying a read reorder queue to give priority scheduling to at least one read command targeting the first memory rank; and executing one or more of the at least one read command on the first memory rank according to the priority scheduling. determining a count of deferred memory refresh operations for the first memory rank; responsive to the count approaching a high priority threshold, issuing an early high priority refresh notification for the first memory rank, wherein the high priority threshold indicates the scheduled time for performing a memory refresh operation as a high priority memory refresh operation at the first memory rank; responsive to the early high priority refresh notification, modifying a read reorder queue to give priority scheduling to at least one read command targeting the first memory rank; and executing one or more of the at least one read command on the first memory rank according to the priority scheduling.