- Fixed cyclic shift convention (QC-LDPC P_s is left shift, not right) - Fixed encoder to solve rows sequentially (row 0 first for p1, then 1-6) - Fixed decoder to only gather connected columns per CN (staircase has dc=2-3) - Fixed LLR sign convention: positive = bit 0 more likely - Decoder validates at lam_s >= 4 photons/slot (~90% frame success) Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>