A nonempty regular route

Within the retained developed regular tube choose a nonzero straight spatial segment of length $\ell$, with enough existing time reserve for the chosen finite protocol and its declared buffers.

For $n\ge 1$, place equal payload registers $A_0,\dots ,A_n$ at equally spaced stations. The payload contains the finite report and every surviving quantum factor that must be returned. Initialize $A_1,\dots ,A_n$ in independent blanks $\omega$, and apply successive SWAPs over developed durations $\ell /n$.