Proposition: Regular reference-preserving transport

Let $n\ge 1$. Place $n+1$ equal payload registers on a straight developed segment of length $\ell >0$ in a convex regular reserve. Initialize all but the source in independent blanks. Successive SWAPs realize the identity payload channel, including every reference. Hop duration $\ell /n$ gives arrival time $\ell$ in geometrized units.

Proof. Each SWAP moves the entire payload and reference correlations to the next register and leaves the old site blank. Induction gives the channel identity; spacing and declared duration give the regular null routes.