diff --git a/sbin/mount_nfs/mount_nfs.8 b/sbin/mount_nfs/mount_nfs.8
index 57b9544e807b..1495caa8ee51 100644
--- a/sbin/mount_nfs/mount_nfs.8
+++ b/sbin/mount_nfs/mount_nfs.8
@@ -124,6 +124,9 @@ service and the
 and
 .Xr rpc.lockd 8
 servers on the client.
+Note that this option will only be honored when performing the
+initial mount, it will be silently ignored if used while updating
+the mount options.
 .It Fl N
 Do
 .Em not