Methods, systems, and devices for wireless communications are described. In some wireless communications systems, a base station may configure a user equipment (UE) to transmit a first message in a set of transmission time intervals (TTIs) of a repetition window, and the base station may configure the same UE or a different UE to transmit a second message in a shortened TTI (sTTI). In such systems, if the base station schedules the transmission of the second message in an sTTI that coincides with at least one overlapping TTI in the set of TTIs of the repetition window, the UE may drop at least a portion of the transmission of the first message in the set of TTIs. Alternatively, the base station may avoid scheduling the uplink transmission of the second message in an sTTI that coincides with a TTI in the set of TTIs of the repetition window.