diff --git a/collect.py b/collect.py
index b41095a..8e28d75 100644
--- a/collect.py
+++ b/collect.py
@@ -192,6 +192,30 @@ def main() -> None:
         metavar="N",
         help="Keep only the last N records per file (default: unlimited)",
     )
+    p.add_argument(
+        "-i", "--interval",
+        type=int,
+        default=None,
+        metavar="SECONDS",
+        help="Collection interval in seconds (overrides credentials file, default: 300)",
+    )
+    p.add_argument(
+        "--host",
+        default=None,
+        help="Push server bind address (overrides credentials file, default: 0.0.0.0)",
+    )
+    p.add_argument(
+        "--port",
+        type=int,
+        default=None,
+        help="Push server TCP port (overrides credentials file, default: 9999)",
+    )
+    p.add_argument(
+        "--log-dir",
+        default=None,
+        metavar="DIR",
+        help="Directory for rotating log files (overrides credentials file, default: ./logs)",
+    )
     p.add_argument("-v", "--verbose", action="store_true", help="Enable debug logging")
     p.add_argument(
         "--diff",
@@ -241,10 +265,14 @@ def main() -> None:
         else:
             args.domains = raw_domains or "charging,measurements,readiness"
 
-    args.interval = int(creds_data.get("interval_s", 300))
-    args.host     = creds_data.get("host", "0.0.0.0")
-    args.port     = int(creds_data.get("port", 9999))
-    args.log_dir  = creds_data.get("log_dir", "./logs")
+    if args.interval is None:
+        args.interval = int(creds_data.get("interval_s", 300))
+    if args.host is None:
+        args.host = creds_data.get("host", "0.0.0.0")
+    if args.port is None:
+        args.port = int(creds_data.get("port", 9999))
+    if args.log_dir is None:
+        args.log_dir = creds_data.get("log_dir", "./logs")
 
     if not args.dry and (not args.username or not args.password):
         p.error(