Δχ² map in DEF gravity space {α₀, β₀} for the simulated dataset (2023–2032) with four campaigns every year. The tests are performed using the DDSTG timing model and assuming stiff MPA1 EOS. The solid lines correspond to the 68% C.L. limits (Δχ² ≃ 2.28). The limit with the blue line is based on the existing TOAs. The blue shade and the orange line are the results for the simulated TOAs that do not account for the Galactic uncertainty in Ṗ_b,xs. The green line shows the corrected limit, with Ṗ_b,xs taken at its 1σ limit. The dashed grey line is the limit from the Solar System Cassini experiment ().