Kristian Evers did this test a few days ago, by removing relevant grids and setting PROJ_NETWORK=OFF:
> echo 55 12 123 2026.3 | cs2cs -d 9 ITRF2020 ETRS89-DNK --only-best > --no-ballpark Attempt to use coordinate operation Conversion from ITRF2020 (geog2D) to ITRF2020 (geocentric) + ITRF2020 to ETRF2014 (1) + ETRF2014 to NKG_ETRF14 (1) + NKG_ETRF14 to ETRS89-DNK (1) + Conversion from ETRS89-DNK (geocentric) to ETRS89-DNK (geog2D) failed. Grid eur_nkg_nkgrf17vel.tif is not available. Consult https://proj.org/resource_files.html for guidance. Rel. 9.8.0, March 2nd, 2026 <cs2cs>: cannot initialize transformation cause: File not found or invalid program abnormally terminated _______________________________________________ PROJ mailing list [email protected] https://lists.osgeo.org/mailman/listinfo/proj
