Methods, systems, and devices for wireless communication are described. A base station may identify a transport block for transmission that includes an information component and an error detection code. The base station may transmit a first encoded message during a first transmission time. The first encoded message may be obtained by encoding the transport block cyclically shifted a first bit length. The base station may transmit a second encoded message during a second transmission time. The second encoded message may be obtained by encoding the transport block cyclically shifted a second bit length. The relative time distance between the first and second transmission times may convey an indication of the difference between the first bit length and the second bit length.