For two fully captured Latin squares LEFT and RIGHT of the SAME order n1..4, rec...
https://datenvertrag.halowerk.com/v1/latin-bitrade-switch-familyOverview
For two fully captured Latin squares LEFT and RIGHT of the SAME order n1..4, reconstruct EVERY NONEMPTY cellmask on which replacing LEFT entries by RIGHT preserves a Latin square. Each original is a flat rowmajor n*n array with symbols0..n-1, each symbol once per row/column; LEFT is REDUCED: its first row AND first column must be0..n-1. RIGHT need not be reduced. ORIGINAL labels are retained; no automatic relabelling. A switchmask may select ONLY cells where left differs from right, bit(r*n+c).