diff --git a/agenda/gwr.py b/agenda/gwr.py
index 6697bfd..992c69f 100644
--- a/agenda/gwr.py
+++ b/agenda/gwr.py
@@ -27,7 +27,7 @@ def extract_weekday_date(html: str) -> date | None:
     return datetime.strptime(date_str, "%A %d %B %Y").date()
 
 
-def advance_tickets_page_html(data_dir: str, ttl: int = 3600) -> str:
+def advance_tickets_page_html(data_dir: str, ttl: int = 60 * 60 * 6) -> str:
     """Get advance-tickets web page HTML with cache."""
     filename = os.path.join(data_dir, "advance-tickets.html")
     url = "https://www.gwr.com/your-tickets/choosing-your-ticket/advance-tickets"