Distance constraint versus timing uncertainty σ_t for GRB 160726A. Blue points show the central solution and 1σ interval for σ_loc = 1 arcsec, while orange and green points show the corresponding 1σ lower limits for σ_loc = 1 arcsec and 3 arcmin once the upper bound becomes unbounded. The horizontal dash-dotted line marks D_center = 3.307 AU. The vertical dotted and dashed lines mark σ_t^crit = |Δt_obs − Δt_∞| and the current timing uncertainty, respectively. The top axis shows the equivalent effective area relative to GBM. This figure illustrates the threshold at which the method changes from yielding only consistency with the infinite-distance limit to directly measuring a finite source distance.