A base station allocates uplink and/or downlink resources (e.g., in the time domain, frequency domain, spatial domain) to user equipment (UEs), or groups of UEs, that are subsequently reallocated. A base station determines a reallocation of uplink resources and/or downlink resources, and issues a cancellation indication or preemption indicator that corresponds to at least a portion of the previously allocated resources. UEs is configured to monitor for cancellation or preemption indicators, and based on received cancellation or preemption indicators, UEs determines whether or not to proceed with an uplink transmission or downlink reception using their previously allocated resources. Rules for application of cancellation or preemption indicators are identified by a UE and/or base station based on traffic prioritization and cancelation indication prioritization, based on types of scheduled reference signals to be transmitted by the UE, etc.