According to some embodiments, a method of decoding a transport block in a wireless network element comprises receiving a first transmission of a transport block. The transport block is modulated according to a first modulation coding scheme. The method further comprises determining a number of soft channel bits SB1 in the first transmission of the transport block based at least on a category type of a wireless device. The category type of wireless device is capable of supporting the first modulation coding scheme and a second modulation coding scheme of a different order than the first modulation scheme and both the first and second modulation schemes are associated with the same number of soft channel bits and soft buffer size. The method further comprises storing SB1 soft channel bits of the first transmission of the transport block in a soft buffer.