The package linux-image-6.18.0-1-librem5 is now available in crimson-updates (since it migrated automatically after a week), but nothing depends on it so far and linux-image-6.12.0-1-librem5 is being installed by default as I haven’t changed the dependency yet. As I said earlier, I plan to have linux-image-librem5 (which is what pulls the actual kernel into the image) point to 6.18 with the next upload if no issues show up meanwhile. This is completely orthogonal to crimson-updates-proposed migrations.
So expect 6.18 to be installed by default in around 2-3 weeks.