diff --git a/.crow/rebuild-abi-gap.yaml b/.crow/rebuild-abi-gap.yaml
index d346adf..289781d 100644
--- a/.crow/rebuild-abi-gap.yaml
+++ b/.crow/rebuild-abi-gap.yaml
@@ -14,9 +14,15 @@
 # minor from CI, only `just rebuild` from a workstation with the S3 and Postgres
 # credentials to hand. This adds that path.
 #
-# `build-one.R --sensitive-only` re-runs the ABI classifier per version, so a
-# package that turns out not to be risky is skipped rather than written into the
-# wrong slot.
+# `--sensitive-only` is deliberately NOT passed. That flag gates on the source
+# classifier, which misses Rcpp: the repair therefore skipped Rcpp entirely,
+# leaving its 4.5-built flat binary as the only copy and breaking every R 4.4
+# client on the slot.
+#
+# Since bincraft v5.3.0 the destination is decided by the built binary's symbols
+# in `upload_single_binary()`, so building unconditionally is safe: a package
+# that needs a per-minor slot lands there, and one that does not lands in the
+# flat slot. Skipping before the build is what removed that decision.
 #
 # Trigger with the slot and an explicit package list:
 #
@@ -207,7 +213,7 @@ steps:
             continue
           fi
           echo "=== rebuilding $$pkg $$ver into $$ABI_R_MINOR ==="
-          "$$RBIN/Rscript" local/build-one.R --sensitive-only "$$pkg" "$$ver" || rc=1
+          "$$RBIN/Rscript" local/build-one.R "$$pkg" "$$ver" || rc=1
         done
         exit $$rc
     backend_options: