Methods, systems, and devices for wireless communications are described. A user equipment (UE) may receive signaling from a base station including a configuration for multiple transmission time intervals (TTIs) including uplink symbols, downlink symbols, flexible symbols, or a combination. The UE may receive a grant scheduling one or more repetitions of an uplink shared channel carrying an uplink random access message from the base station. The UE may determine available TTIs for the repetitions based on a pre-TTI evaluation of symbols according to a rule that defines types of symbols available for the uplink shared channel. The UE may transmit the repetitions on the available TTIs according to the rule.