A video coding mechanism is disclosed. The mechanism includes encoding a bitstream comprising a video parameter set (VPS) and one or more sublayers. A buffering period (BP) supplemental enhancement information (SEI) message comprising a BP maximum sublayers minus one (bp_max_sublayers_minus1) is also encoded into the bitstream. The bp_max_sublayers_minus1 is set to a value in a range of zero to a maximum number of sublayers indicated in the VPS. A hypothetical reference decoder (HRD) is initialized based on the BP SEI message. A set of bitstream conformance tests are performed on the sublayers. The bitstream is stored for communication toward a decoder.