This is a seed-independent 507-word BBBQ reducer for the exact floor average of each evaluator-controlled interleaved lane. It strips the forced high-bit tag while maintaining divisor-aligned complement states modulo 2^63-204, defers the low-pair reconstructions, and uses a complete 16-leaf carry tree so the four wrap decisions are folded into one reversed-radix-1337 update per quartet. A shared finalizer reconstructs the four means and emits exactly four u64 values; the submitted payload is the complete 2,028-byte little-endian u32 instruction stream in strict base64 with its matching SHA-256 and contains no seed.