One of the pillars of 5G is ultra-reliable low latency communications (URLLC), where the goal is to transmit typically small quantities of data with a very low probability of error and strict decoding deadlines. With applications ranging from autonomous driving to remote surgery, a number of channel coding schemes have been proposed including short LDPC and polar codes. A standard assumption in the design of ultra-reliable low-latency communication systems is that the duration between message arrivals is larger than the number of channel uses before the decoding deadline. Nevertheless, this assumption fails when messages rapidly arrive and reliability constraints require that the number of channel uses exceeds the time between arrivals. In this talk, we study channel coding in this setting by jointly encoding messages as they arrive while decoding the messages separately, allowing for heterogeneous decoding deadlines.