diff --git a/src/Service/Rtt/RttRecoveryComputationService.php b/src/Service/Rtt/RttRecoveryComputationService.php
index 37a56aa..ebd4b5b 100644
--- a/src/Service/Rtt/RttRecoveryComputationService.php
+++ b/src/Service/Rtt/RttRecoveryComputationService.php
@@ -413,10 +413,17 @@ final readonly class RttRecoveryComputationService
     {
         $total = 0;
         foreach ($days as $date) {
-            $isoDay     = (int) new DateTimeImmutable($date)->format('N');
-            $contract   = $contractsByDate[$date] ?? null;
-            $hours      = $contract?->getWeeklyHours();
-            $startHours = (null !== $hours && $hours >= 39) ? 39 : 35;
+            $isoDay   = (int) new DateTimeImmutable($date)->format('N');
+            $contract = $contractsByDate[$date] ?? null;
+            $hours    = $contract?->getWeeklyHours();
+            // Days without an active contract (pre-hire, post-termination, contract
+            // gaps) must NOT contribute to the weekly 25% overtime threshold —
+            // otherwise hiring mid-week artificially inflates the threshold and
+            // erases legitimate overtime.
+            if (null === $hours || $hours <= 0) {
+                continue;
+            }
+            $startHours = $hours >= 39 ? 39 : 35;
             $total += $this->resolveDailyReferenceMinutes($startHours, $isoDay);
         }