diff --git a/internal/config/store_postgres.go b/internal/config/store_postgres.go
index 5dc57909..e19fdacd 100644
--- a/internal/config/store_postgres.go
+++ b/internal/config/store_postgres.go
@@ -728,6 +728,9 @@ func advanceRampStep(ctx context.Context, tx pgx.Tx, plan *PurchasePlan, stepNum
 // next_execution_date at the step after it (or clearing it on a finished ramp)
 // and stamping the execution timestamps.
 func (s *PostgresStore) persistRampPosition(ctx context.Context, tx pgx.Tx, plan *PurchasePlan) error {
+	if plan.RampSchedule.DatesManaged {
+		return s.persistManagedRampPosition(ctx, tx, plan)
+	}
 	if plan.RampSchedule.IsComplete() {
 		plan.NextExecutionDate = nil
 	} else {
diff --git a/internal/config/store_postgres_plan_schedule_clock.go b/internal/config/store_postgres_plan_schedule_clock.go
new file mode 100644
index 00000000..820ee1d6
--- /dev/null
+++ b/internal/config/store_postgres_plan_schedule_clock.go
@@ -0,0 +1,127 @@
+package config
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/jackc/pgx/v5"
+)
+
+func (s *PostgresStore) persistManagedRampPosition(ctx context.Context, tx pgx.Tx, plan *PurchasePlan) error {
+	next, err := s.planScheduleNextDateTx(ctx, tx, plan)
+	if err != nil {
+		return err
+	}
+	now := time.Now()
+	var updated time.Time
+	err = tx.QueryRow(ctx, `UPDATE purchase_plans SET
+		ramp_schedule = jsonb_set(ramp_schedule, '{current_step}', to_jsonb($2::int)),
+		next_execution_date = $3, last_execution_date = $4
+		WHERE id = $1 AND updated_at = $5 RETURNING updated_at`,
+		plan.ID, plan.RampSchedule.CurrentStep, next, now, plan.UpdatedAt).Scan(&updated)
+	if errors.Is(err, pgx.ErrNoRows) {
+		return ErrPurchasePlanConflict
+	}
+	if err != nil {
+		return fmt.Errorf("persist managed ramp position: %w", err)
+	}
+	plan.NextExecutionDate, plan.LastExecutionDate, plan.UpdatedAt = next, &now, updated
+	return nil
+}
+
+func (s *PostgresStore) planScheduleNextDateTx(ctx context.Context, tx pgx.Tx, plan *PurchasePlan) (*time.Time, error) {
+	if plan.RampSchedule.IsComplete() {
+		return nil, nil
+	}
+	if !plan.RampSchedule.DatesManaged {
+		next := plan.RampSchedule.GetNextPurchaseDate()
+		return &next, nil
+	}
+	root, err := s.managedPlanNextRootTx(ctx, tx, plan)
+	if err != nil || root == nil {
+		return nil, err
+	}
+	return &root.ScheduledDate, nil
+}
+
+func (s *PostgresStore) managedPlanNextRootTx(ctx context.Context, tx pgx.Tx, plan *PurchasePlan) (*PurchaseExecution, error) {
+	rows, err := s.ListExecutionsForPlanStepTx(ctx, tx, plan.ID, plan.RampSchedule.CurrentStep+1)
+	if err != nil {
+		return nil, err
+	}
+	root, err := managedPlanNextRoot(plan, rows)
+	if err != nil || root == nil {
+		return nil, err
+	}
+	var incoming bool
+	if err := tx.QueryRow(ctx, `SELECT EXISTS (SELECT 1 FROM purchase_executions WHERE retry_execution_id = $1)`, root.ExecutionID).Scan(&incoming); err != nil {
+		return nil, fmt.Errorf("check managed root retry references: %w", err)
+	}
+	if incoming {
+		return nil, nil
+	}
+	return root, nil
+}
+
+func managedPlanNextRoot(plan *PurchasePlan, rows []PurchaseExecution) (*PurchaseExecution, error) {
+	var root *PurchaseExecution
+	blocked := false
+	for i := range rows {
+		row := &rows[i]
+		if row.StepNumber != plan.RampSchedule.CurrentStep+1 {
+			continue
+		}
+		if row.Status == StatusCanceled || row.Status == LegacyStatusCanceled {
+			blocked = blocked || managedRootPriorAction(row)
+			continue
+		}
+		if !managedRootIdentity(row) {
+			blocked = true
+			continue
+		}
+		if root != nil {
+			return nil, fmt.Errorf("%w: duplicate managed roots for step %d", ErrPurchasePlanConflict, row.StepNumber)
+		}
+		root = row
+	}
+	if blocked || !managedRootClockAvailable(root) {
+		return nil, nil
+	}
+	return root, nil
+}
+
+func managedRootIdentity(row *PurchaseExecution) bool {
+	lineage := row.IdempotencyKey
+	if lineage == "" {
+		lineage = row.ExecutionID
+	}
+	return row.CloudAccountID == nil && row.RetryAttemptN == 0 && row.RetryExecutionID == nil && !strings.Contains(lineage, ":")
+}
+
+func managedRootPriorAction(row *PurchaseExecution) bool {
+	if row.ExecutedAt != nil || row.CompletedAt != nil || row.PreApprovalSkipReason != nil && *row.PreApprovalSkipReason != "" {
+		return true
+	}
+	for i := range row.Recommendations {
+		if row.Recommendations[i].Purchased {
+			return true
+		}
+	}
+	return false
+}
+
+func managedRootClockAvailable(row *PurchaseExecution) bool {
+	if row == nil || row.ScheduledDate.IsZero() || managedRootPriorAction(row) {
+		return false
+	}
+	switch row.Status {
+	case "pending", "notified":
+		return row.ScheduledExecutionAt == nil
+	case "scheduled":
+		return row.ScheduledExecutionAt != nil && !row.ScheduledExecutionAt.IsZero()
+	}
+	return false
+}
diff --git a/internal/config/store_postgres_plan_schedule_clock_integration_test.go b/internal/config/store_postgres_plan_schedule_clock_integration_test.go
new file mode 100644
index 00000000..28e5c557
--- /dev/null
+++ b/internal/config/store_postgres_plan_schedule_clock_integration_test.go
@@ -0,0 +1,188 @@
+//go:build integration
+
+package config
+
+import (
+	"context"
+	"encoding/json"
+	"testing"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/jackc/pgx/v5"
+	"github.com/stretchr/testify/require"
+)
+
+func managedClockFixture(ctx context.Context, t *testing.T, current int) *rampFixture {
+	t.Helper()
+	f := newRampFixture(ctx, t, 0, current, 3)
+	_, err := f.store.db.Exec(ctx, `UPDATE purchase_plans SET
+		ramp_schedule = ramp_schedule || '{"dates_managed":true,"future_metadata":{"nested":9007199254740993}}',
+		services = '{"future_service":{"enabled":false,"unknown_filter":["retained"]}}',
+		ramp_baseline = '{"frozen":{"count":97}}' WHERE id = $1`, f.planID)
+	require.NoError(t, err)
+	return f
+}
+
+func nextClockRoot(ctx context.Context, t *testing.T, f *rampFixture, status string) *PurchaseExecution {
+	t.Helper()
+	root := f.row(ctx, t, 3, nil, status)
+	date := time.Now().UTC().Truncate(24*time.Hour).AddDate(0, 0, 47)
+	_, err := f.store.db.Exec(ctx, `UPDATE purchase_executions SET scheduled_date = $2 WHERE execution_id = $1`, root.ExecutionID, date)
+	require.NoError(t, err)
+	root.ScheduledDate = date
+	return root
+}
+
+func TestManagedCompletionKeepsNextRootAndRawPlan(t *testing.T) {
+	for _, targetMet := range []bool{false, true} {
+		t.Run(map[bool]string{false: "bought", true: "target met"}[targetMet], func(t *testing.T) {
+			ctx := context.Background()
+			f := managedClockFixture(ctx, t, 1)
+			root := nextClockRoot(ctx, t, f, "pending")
+			heldRec := baselineRec(uuid.NewString(), "m5.large", 17)
+			f.rowWithRecs(ctx, t, 1, nil, StatusCompleted, false, heldRec)
+			var before []byte
+			heldBefore := f.committed(ctx, t)
+			require.Equal(t, 17, heldBefore[baselineKey(t, heldRec)].Count)
+			require.NoError(t, f.store.db.QueryRow(ctx, `SELECT jsonb_build_object('services',services,'baseline',ramp_baseline,
+				'metadata',ramp_schedule->'future_metadata') FROM purchase_plans WHERE id=$1`, f.planID).Scan(&before))
+			if targetMet {
+				current := f.row(ctx, t, 2, nil, "pending")
+				require.NoError(t, f.store.WithTx(ctx, func(tx pgx.Tx) error {
+					return f.store.CompleteTargetMetStepTx(ctx, tx, f.planID, 2, current.ExecutionID, "target already held")
+				}))
+			} else {
+				f.row(ctx, t, 2, nil, StatusCompleted)
+				require.NoError(t, f.store.CompletePlanStep(ctx, f.planID, 2))
+			}
+			plan, err := f.store.GetPurchasePlan(ctx, f.planID)
+			require.NoError(t, err)
+			require.Equal(t, 2, plan.RampSchedule.CurrentStep)
+			require.NotNil(t, plan.NextExecutionDate)
+			require.True(t, root.ScheduledDate.Equal(*plan.NextExecutionDate), "completion must retain the exact next managed root date")
+			var after []byte
+			require.NoError(t, f.store.db.QueryRow(ctx, `SELECT jsonb_build_object('services',services,'baseline',ramp_baseline,
+				'metadata',ramp_schedule->'future_metadata') FROM purchase_plans WHERE id=$1`, f.planID).Scan(&after))
+			require.Equal(t, before, after)
+			require.Equal(t, heldBefore, f.committed(ctx, t))
+			var ramp map[string]json.RawMessage
+			require.NoError(t, f.store.db.QueryRow(ctx, `SELECT ramp_schedule FROM purchase_plans WHERE id=$1`, f.planID).Scan(&after))
+			require.NoError(t, json.Unmarshal(after, &ramp))
+			require.JSONEq(t, "true", string(ramp["dates_managed"]))
+		})
+	}
+}
+
+func TestManagedCompletionStopsAtBlockedNextRoot(t *testing.T) {
+	cases := []struct {
+		name, status, sql string
+		extra             string
+		conflict, healthy bool
+	}{
+		{name: "missing"},
+		{name: "canceled", status: StatusCanceled},
+		{name: "failed", status: StatusFailed},
+		{name: "paused", status: "paused"},
+		{name: "legacy uncertain", status: "approved"},
+		{name: "duplicate", status: "pending", extra: "duplicate", conflict: true},
+		{name: "zero date", status: "pending", sql: "scheduled_date='0001-01-01T00:00:00Z'"},
+		{name: "scheduled without delayed fire", status: "scheduled"},
+		{name: "pending delayed fire", status: "pending", sql: "scheduled_execution_at=NOW()"},
+		{name: "executed", status: "pending", sql: "executed_at=NOW()"},
+		{name: "completed provenance", status: "pending", sql: "completed_at=NOW()"},
+		{name: "skip provenance", status: "pending", sql: "pre_approval_skip_reason='unknown'"},
+		{name: "purchased provenance", status: "pending", sql: `recommendations='[{"purchased":true}]'`},
+		{name: "canceled purchased predecessor", status: "pending", extra: "canceled purchased"},
+		{name: "canceled executed predecessor", status: "pending", extra: "canceled executed"},
+		{name: "live child", status: "pending", extra: "child"},
+		{name: "incoming other step", status: "pending", extra: "incoming step"},
+		{name: "incoming other plan", status: "pending", extra: "incoming plan"},
+		{name: "canceled unacted replacement", status: "pending", extra: "canceled", healthy: true},
+		{name: "scheduled trustworthy", status: "scheduled", sql: "scheduled_execution_at=NOW()+INTERVAL '48 days'", healthy: true},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			ctx := context.Background()
+			f := managedClockFixture(ctx, t, 1)
+			f.row(ctx, t, 2, nil, StatusCompleted)
+			var root *PurchaseExecution
+			if tc.status != "" {
+				root = nextClockRoot(ctx, t, f, tc.status)
+				if tc.sql != "" {
+					_, err := f.store.db.Exec(ctx, "UPDATE purchase_executions SET "+tc.sql+" WHERE execution_id=$1", root.ExecutionID)
+					require.NoError(t, err)
+				}
+			}
+			managedClockSibling(ctx, t, f, root, tc.extra)
+			err := f.store.CompletePlanStep(ctx, f.planID, 2)
+			if tc.conflict {
+				require.ErrorIs(t, err, ErrPurchasePlanConflict)
+				require.Equal(t, 1, f.currentStep(ctx, t))
+				return
+			}
+			require.NoError(t, err)
+			plan, err := f.store.GetPurchasePlan(ctx, f.planID)
+			require.NoError(t, err)
+			require.Equal(t, 2, plan.RampSchedule.CurrentStep)
+			if tc.healthy {
+				require.NotNil(t, plan.NextExecutionDate)
+				require.True(t, root.ScheduledDate.Equal(*plan.NextExecutionDate))
+			} else {
+				require.Nil(t, plan.NextExecutionDate, "blocked next root must stop the managed clock")
+			}
+		})
+	}
+}
+
+func managedClockSibling(ctx context.Context, t *testing.T, f *rampFixture, root *PurchaseExecution, extra string) {
+	t.Helper()
+	if extra == "" {
+		return
+	}
+	status := StatusCanceled
+	if extra == "duplicate" || extra == "child" || extra == "incoming step" || extra == "incoming plan" {
+		status = "pending"
+	}
+	owner, step := f, 3
+	if extra == "incoming step" {
+		step = 1
+	}
+	if extra == "incoming plan" {
+		other, err := f.store.GetPurchasePlan(ctx, f.planID)
+		require.NoError(t, err)
+		other.ID, other.Name = "", "Other "+uuid.NewString()[:8]
+		require.NoError(t, f.store.CreatePurchasePlan(ctx, other))
+		owner = &rampFixture{store: f.store, planID: other.ID}
+	}
+	sibling := owner.row(ctx, t, step, nil, status)
+	var err error
+	switch extra {
+	case "child":
+		_, err = f.store.db.Exec(ctx, `UPDATE purchase_executions SET retry_attempt_n=1 WHERE execution_id=$1`, sibling.ExecutionID)
+	case "canceled purchased":
+		_, err = f.store.db.Exec(ctx, `UPDATE purchase_executions SET recommendations='[{"purchased":true}]' WHERE execution_id=$1`, sibling.ExecutionID)
+	case "canceled executed":
+		_, err = f.store.db.Exec(ctx, `UPDATE purchase_executions SET executed_at=NOW() WHERE execution_id=$1`, sibling.ExecutionID)
+	case "incoming step", "incoming plan":
+		_, err = f.store.db.Exec(ctx, `UPDATE purchase_executions SET retry_execution_id=$2 WHERE execution_id=$1`, sibling.ExecutionID, root.ExecutionID)
+	}
+	require.NoError(t, err)
+}
+
+func TestManagedCompletionFinishedAndLegacyClock(t *testing.T) {
+	ctx := context.Background()
+	f := managedClockFixture(ctx, t, 2)
+	f.row(ctx, t, 3, nil, StatusCompleted)
+	require.NoError(t, f.store.CompletePlanStep(ctx, f.planID, 3))
+	plan, err := f.store.GetPurchasePlan(ctx, f.planID)
+	require.NoError(t, err)
+	require.Nil(t, plan.NextExecutionDate)
+	legacy := newRampFixture(ctx, t, 0, 1, 3)
+	legacy.row(ctx, t, 2, nil, StatusCompleted)
+	require.NoError(t, legacy.store.CompletePlanStep(ctx, legacy.planID, 2))
+	plan, err = legacy.store.GetPurchasePlan(ctx, legacy.planID)
+	require.NoError(t, err)
+	require.NotNil(t, plan.NextExecutionDate)
+	require.WithinDuration(t, plan.RampSchedule.GetNextPurchaseDate(), *plan.NextExecutionDate, time.Millisecond) // Postgres stores microseconds
+}
diff --git a/internal/config/types.go b/internal/config/types.go
index 31e0cd5c..80a650e8 100644
--- a/internal/config/types.go
+++ b/internal/config/types.go
@@ -254,6 +254,7 @@ type RampSchedule struct {
 	CurrentStep      int       `json:"current_step" dynamodbav:"current_step"`
 	TotalSteps       int       `json:"total_steps" dynamodbav:"total_steps"`
 	StartDate        time.Time `json:"start_date" dynamodbav:"start_date"`
+	DatesManaged     bool      `json:"dates_managed,omitempty" dynamodbav:"dates_managed,omitempty"`
 }
 
 // PresetRampSchedules provides common ramp-up configurations.