diff --git a/modules/mesh-delivery-builder/cmd/mesh-delivery-builder/integration_test.go b/modules/mesh-delivery-builder/cmd/mesh-delivery-builder/integration_test.go
index ebbc9ee5..eee4c068 100644
--- a/modules/mesh-delivery-builder/cmd/mesh-delivery-builder/integration_test.go
+++ b/modules/mesh-delivery-builder/cmd/mesh-delivery-builder/integration_test.go
@@ -9,6 +9,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"maps"
 	"os"
 	"path/filepath"
 	"slices"
@@ -613,6 +614,29 @@ func TestBuilderMakesADoneKeyWithTheDigests(t *testing.T) { // 1607/AC7
 	if a := reg.answered(t, key, again); a.Refused || a.Do != versions.AgainRenumber || a.Version != "0.1.6" {
 		t.Errorf("builder_publish_again = %+v, want a new number, 0.1.6", a)
 	}
+	// Running-testing note (review round 1): two claims never get one number on the bus's own compare-and-set, as
+	// the builder's state versions keeps them: eight claims of one name at once, eight versions.
+	store := versions.Versions{Store: awaitedVersions{process.AwaitBucket(b.ctx, b.js, nil, versions.Bucket, "", t.Logf)}}
+	numbers := make(chan string, 8)
+	var claims sync.WaitGroup
+	for i := range 8 {
+		claims.Go(func() {
+			d, _, err := store.Number(b.ctx, versions.Claim{Name: "netcheck/race", Kind: versions.KindBundle, Fingerprint: fmt.Sprintf("f%d", i)})
+			if err != nil {
+				t.Error(err)
+			}
+			numbers <- d.Version
+		})
+	}
+	claims.Wait()
+	close(numbers)
+	got := map[string]bool{}
+	for v := range numbers {
+		got[v] = true
+	}
+	if len(got) != 8 {
+		t.Errorf("eight claims of one name at once were numbered %v, want eight versions", slices.Sorted(maps.Keys(got)))
+	}
 	if got := reg.numberedOf("netcheck/tools-go"); len(got) != 2 || got[1] != "0.1.6" {
 		t.Errorf("version.numbered of netcheck/tools-go = %v, want 0.1.6 said after 0.1.5", got)
 	}