diff --git a/src/Controller/Booking/Create/Step2Controller.php b/src/Controller/Booking/Create/Step2Controller.php
index cadb6f6..133a278 100644
--- a/src/Controller/Booking/Create/Step2Controller.php
+++ b/src/Controller/Booking/Create/Step2Controller.php
@@ -138,9 +138,8 @@ class Step2Controller extends AbstractController
             throw $this->createNotFoundException(sprintf('Participant at index %d does not exist', $index));
         }
 
-        // Fetch fresh availabilities when entering participant form
-        // This ensures up-to-date data and populates cache for subsequent HTMX refreshes
-        $this->travelDataService->enrichWithFreshAvailabilities($bookingDto->travel, cached: false);
+        // Use cached availability data (populated during booking init)
+        $this->travelDataService->enrichWithFreshAvailabilities($bookingDto->travel);
 
         // Create form with booking_context option
         $form = $this->createParticipantForm($bookingDto, $index);
diff --git a/src/Controller/Booking/Edit/IndexController.php b/src/Controller/Booking/Edit/IndexController.php
index 05e9404..5fdf5bd 100644
--- a/src/Controller/Booking/Edit/IndexController.php
+++ b/src/Controller/Booking/Edit/IndexController.php
@@ -168,9 +168,8 @@ class IndexController extends AbstractController
             return $this->redirectToRoute('app_booking_edit', ['id' => $id]);
         }
 
-        // Fetch fresh availabilities when entering participant form
-        // This ensures up-to-date data and populates cache for subsequent HTMX refreshes
-        $this->travelDataService->enrichWithFreshAvailabilities($bookingDto->travel, cached: false);
+        // Use cached availability data (populated during booking init)
+        $this->travelDataService->enrichWithFreshAvailabilities($bookingDto->travel);
 
         // Create wrapper DTO for email uniqueness validation
         $wrapper = new ParticipantEditDto(
diff --git a/src/Service/BookingEditDataLoaderService.php b/src/Service/BookingEditDataLoaderService.php
index 55c397b..c231d21 100644
--- a/src/Service/BookingEditDataLoaderService.php
+++ b/src/Service/BookingEditDataLoaderService.php
@@ -75,7 +75,8 @@ class BookingEditDataLoaderService
         }
 
         $mutableData = $this->travelDataService->getMutabilityData($bookingData->dateId);
-        $availabilities = $this->travelDataService->getAvailabilityData($bookingData->dateId);
+        // Using cached: true populates the cache for subsequent participant form loads
+        $availabilities = $this->travelDataService->getAvailabilityData($bookingData->dateId, cached: true);
 
         if (null === $mutableData || null === $availabilities) {
             return null;
diff --git a/src/Service/BookingService.php b/src/Service/BookingService.php
index 5a58229..dbb83d7 100644
--- a/src/Service/BookingService.php
+++ b/src/Service/BookingService.php
@@ -236,7 +236,8 @@ class BookingService
         }
 
         // Fetch and patch availability data (includes allowedBookingStatus from API)
-        $availabilities = $this->travelDataService->getAvailabilityData($dateId);
+        // Using cached: true populates the cache for subsequent participant form loads
+        $availabilities = $this->travelDataService->getAvailabilityData($dateId, cached: true);
         if (null !== $availabilities) {
             $this->travelDataService->patchAvailabilities($travelData, $availabilities);
         }
diff --git a/src/Service/TravelDataService.php b/src/Service/TravelDataService.php
index 2996fa3..03ea4b0 100644
--- a/src/Service/TravelDataService.php
+++ b/src/Service/TravelDataService.php
@@ -523,19 +523,18 @@ class TravelDataService
      * Gets availability data for a travel date.
      *
      * @param int  $dateId The travel date ID for API call
-     * @param bool $cached Whether to use cached data (default: false, TTL when cached: 300 seconds)
-     * @param int  $ttl    Cache TTL in seconds when $cached is true (default: 300 seconds)
+     * @param bool $cached Whether to use cached data (default: false, TTL when cached: 600 seconds)
+     * @param int  $ttl    Cache TTL in seconds when $cached is true (default: 600 seconds)
      *
      * @return ServiceAvailabilityResponse|null The availability data or null if not available or error occurred
      */
-    public function getAvailabilityData(int $dateId, bool $cached = false, int $ttl = 300): ?ServiceAvailabilityResponse
+    public function getAvailabilityData(int $dateId, bool $cached = false, int $ttl = 600): ?ServiceAvailabilityResponse
     {
         if ($cached) {
             $cacheKey = sprintf('availability_%d', $dateId);
 
             try {
                 return $this->cache->get($cacheKey, function (ItemInterface $item) use ($dateId, $ttl) {
-                    // Short TTL - availability is volatile and changes with bookings
                     $item->expiresAfter($ttl);
 
                     return $this->fetchAvailabilityData($dateId);