Upper frame: Gaia DR3 CMD with G_BP − G_RP colour; lower frame: Gaia DR3 CMD with G − G_RP colour; for 2 000 000 randomly selected objects with parallax errors less than 10% (grey dots), and the subset of halo candidates with tangential velocities greater than 145 km s⁻¹ (green dots). C24 BHB candidates (cyan dots). BHB candidates with CPM partner candidates (blue triangles), and CPM partner candidates (magenta diamonds). The only BHB candidate – CPM partner candidate pair where both pass the parallax error < 20% criterion are joined with a bold yellow line in both the upper and lower frames.