diff --git a/api/api.go b/api/api.go
index eaae377..eefa826 100644
--- a/api/api.go
+++ b/api/api.go
@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"io"
 	"net/http"
-	"time"
 
 	"github.com/kr/pretty"
 	"golang.org/x/exp/slices"
@@ -16,7 +15,6 @@ import (
 	"tier.run/refs"
 	"tier.run/stripe"
 	"tier.run/trweb"
-	"tier.run/values"
 )
 
 func init() {
@@ -246,7 +244,7 @@ func (h *Handler) serveReport(w http.ResponseWriter, r *http.Request) error {
 
 	return h.c.ReportUsage(r.Context(), rr.Org, rr.Feature, control.Report{
 		N:       rr.N,
-		At:      values.Coalesce(rr.At, time.Now()),
+		At:      rr.At,
 		Clobber: rr.Clobber,
 	})
 }
diff --git a/api/api_test.go b/api/api_test.go
index 4d6a165..b707d7a 100644
--- a/api/api_test.go
+++ b/api/api_test.go
@@ -406,7 +406,11 @@ func TestTierReport(t *testing.T) {
 	t.Parallel()
 
 	ctx := context.Background()
-	tc, _ := newTestClient(t)
+	tc, cc := newTestClient(t)
+
+	farIntoTheFuture := time.Now().Add(24 * time.Hour)
+	clock := stroke.NewClock(t, cc.Stripe, t.Name(), farIntoTheFuture)
+	cc.Clock = clock.ID()
 
 	pr, err := tc.PushJSON(ctx, []byte(`
 		{
@@ -436,14 +440,8 @@ func TestTierReport(t *testing.T) {
 	}
 
 	if err := tc.ReportUsage(ctx, "org:test", "feature:t", 10, &tier.ReportParams{
-		// Report the usage at a time in the near future to avoid
-		// complaints from Stripe about being too early (e.g. the same
-		// start time as the current phase) or too late (e.g. > 5mins
-		// into the future.
-		//
-		// If this test becomes flaky, we should use Test Clocks. For
-		// now, avoid the slowness of the Test Clock API.
-		At: time.Now().Add(1 * time.Minute),
+		// Force 'now' at Stripe.
+		At: time.Time{}, // for 'now' on the server
 
 		Clobber: false,
 	}); err != nil {
diff --git a/client/tier/client.go b/client/tier/client.go
index cd298b6..d5aed74 100644
--- a/client/tier/client.go
+++ b/client/tier/client.go
@@ -239,7 +239,6 @@ func (c *Client) Subscribe(ctx context.Context, org string, featuresAndPlans ...
 		Org:    org,
 		Phases: []apitypes.Phase{{Features: featuresAndPlans}},
 	})
-
 	return err
 }
 
diff --git a/cmd/tier/tier.go b/cmd/tier/tier.go
index 3fe83c6..2d28d41 100644
--- a/cmd/tier/tier.go
+++ b/cmd/tier/tier.go
@@ -408,7 +408,6 @@ func runTier(cmd string, args []string) (err error) {
 			return err
 		}
 		return tc().ReportUsage(ctx, org, feature, n, &tier.ReportParams{
-			At:      time.Now(),
 			Clobber: *clobber,
 		})
 	case "whoami":