diff --git a/reference/tiflash/upgrade.md b/reference/tiflash/upgrade.md
index 80860bc3d4c35..e558cb2a28da5 100644
--- a/reference/tiflash/upgrade.md
+++ b/reference/tiflash/upgrade.md
@@ -6,7 +6,11 @@ category: reference
 
 # Upgrade TiFlash Nodes
 
-To upgrade TiFlash nodes, take the following steps:
+> **Note:**
+>
+> To upgrade TiFlash from the Pre-RC version to a later version, contact [PingCAP](mailto:info@pingcap.com) for more information and help.
+
+Before the upgrade, make sure that the cluster is started. To upgrade TiFlash nodes, take the following steps:
 
 1. Back up the `tidb-ansible` folder: