diff --git a/javaTest/outputs/wcs-history-driven-center-dispatch-20260731/manifest.sha256 b/javaTest/outputs/wcs-history-driven-center-dispatch-20260731/manifest.sha256
index 2e9ae71..16ed633 100644
--- a/javaTest/outputs/wcs-history-driven-center-dispatch-20260731/manifest.sha256
+++ b/javaTest/outputs/wcs-history-driven-center-dispatch-20260731/manifest.sha256
@@ -1,5 +1,5 @@
 ce2887fae1259726a10d3341752f469270131f84131469cfded451c70584b50d  invariant-results.json
-b723ca025912805ae1616db6498f64292c0a5398704299befb230b749fa53c77  readable-report.xlsx
+93699864fdb9bfad5cd7f3238341907a8e2552fb6df76c0c7857b85dc306c037  readable-report.xlsx
 e0be7cc804c2376617baeaa83554d0980bacad6af59866f7f651883dd5546007  summary.json
 4f619b1eaeba4eda13ebbb0fd86577ccfb7308aa7a9d5cb78bb57bdc3ab0c608  task-results.csv
 30694b474a3a4af2bf269903a21a817dafce860b445def1429595d5ee975dbb2  tick-events.csv
diff --git a/javaTest/outputs/wcs-history-driven-center-dispatch-20260731/readable-report.xlsx b/javaTest/outputs/wcs-history-driven-center-dispatch-20260731/readable-report.xlsx
index 80e6306..6120155 100644
Binary files a/javaTest/outputs/wcs-history-driven-center-dispatch-20260731/readable-report.xlsx and b/javaTest/outputs/wcs-history-driven-center-dispatch-20260731/readable-report.xlsx differ
diff --git a/javaTest/src/main/java/com/ft546/wcs/shadow/history/simulation/HistoricalDispatchSimulator.java b/javaTest/src/main/java/com/ft546/wcs/shadow/history/simulation/HistoricalDispatchSimulator.java
index 79ff624..5ce1205 100644
--- a/javaTest/src/main/java/com/ft546/wcs/shadow/history/simulation/HistoricalDispatchSimulator.java
+++ b/javaTest/src/main/java/com/ft546/wcs/shadow/history/simulation/HistoricalDispatchSimulator.java
@@ -100,7 +100,8 @@ public final class HistoricalDispatchSimulator {
                     events, traversedEdges);
             verifyLedger(ledger, invariants);
 
-            boolean awaitingFutureArrival = active.isEmpty() && clearanceMoves.isEmpty()
+            boolean awaitingFutureArrival = queue.size() > 0
+                    && active.isEmpty() && clearanceMoves.isEmpty()
                     && queue.readyAt(now).isEmpty();
             if (watchdog.observe(terminal.size(),
                     businessProgress || clearanceProgress.moved || awaitingFutureArrival,
@@ -461,7 +462,7 @@ public final class HistoricalDispatchSimulator {
             ResourceKey edge = ResourceKey.edge(from, to);
             List<ResourceKey> resources = Arrays.asList(
                     ResourceKey.node(from), edge, ResourceKey.node(to));
-            Instant decisionTime = Instant.EPOCH.plusMillis(now + tick);
+            Instant decisionTime = Instant.EPOCH.plusMillis(now);
             TrafficVehicleSnapshot frozen = new TrafficVehicleSnapshot(vehicleId,
                     Long.toString(vehicle.getBootId()), tick + 1, tick + 1,
                     decisionTime, from, to,
diff --git a/javaTest/src/main/java/com/ft546/wcs/shadow/history/simulation/SimulationClock.java b/javaTest/src/main/java/com/ft546/wcs/shadow/history/simulation/SimulationClock.java
index 0f063d4..7f45d64 100644
--- a/javaTest/src/main/java/com/ft546/wcs/shadow/history/simulation/SimulationClock.java
+++ b/javaTest/src/main/java/com/ft546/wcs/shadow/history/simulation/SimulationClock.java
@@ -27,15 +27,10 @@ public final class SimulationClock {
         Collections.sort(ordered);
         LinkedHashMap<LocalDateTime, Long> converted =
                 new LinkedHashMap<LocalDateTime, Long>();
-        long simulationMillis = 0L;
-        LocalDateTime previous = null;
+        LocalDateTime first = ordered.get(0);
         for (LocalDateTime arrival : ordered) {
-            if (previous != null) {
-                long sourceGap = Duration.between(previous, arrival).toMillis();
-                simulationMillis += sourceGap / acceleration;
-            }
+            long simulationMillis = Duration.between(first, arrival).toMillis() / acceleration;
             converted.put(arrival, simulationMillis);
-            previous = arrival;
         }
         this.arrivals = Collections.unmodifiableMap(converted);
     }
diff --git a/javaTest/src/test/java/com/ft546/wcs/shadow/history/simulation/SimulationClockTest.java b/javaTest/src/test/java/com/ft546/wcs/shadow/history/simulation/SimulationClockTest.java
index 401728b..c4b1cfd 100644
--- a/javaTest/src/test/java/com/ft546/wcs/shadow/history/simulation/SimulationClockTest.java
+++ b/javaTest/src/test/java/com/ft546/wcs/shadow/history/simulation/SimulationClockTest.java
@@ -31,4 +31,17 @@ class SimulationClockTest {
         assertThrows(IllegalArgumentException.class,
                 () -> new SimulationClock(Arrays.asList(base), 25));
     }
+
+    @Test
+    void scalesFromTheFirstArrivalWithoutAccumulatingRoundingLoss() {
+        LocalDateTime base = LocalDateTime.of(2026, 3, 1, 10, 0);
+        LocalDateTime firstGap = base.plusNanos(99_000_000L);
+        LocalDateTime secondGap = base.plusNanos(198_000_000L);
+
+        SimulationClock clock = new SimulationClock(
+                Arrays.asList(base, firstGap, secondGap), 100);
+
+        assertEquals(0L, clock.toSimulationMillis(firstGap));
+        assertEquals(1L, clock.toSimulationMillis(secondGap));
+    }
 }