diff --git a/doc/advanced/config-cheat-sheet.en-us.md b/doc/advanced/config-cheat-sheet.en-us.md
index 2dae3526..edd23012 100644
--- a/doc/advanced/config-cheat-sheet.en-us.md
+++ b/doc/advanced/config-cheat-sheet.en-us.md
@@ -1095,7 +1095,7 @@ Task queue configuration has been moved to `queue.task`. However, the below conf
 
 ## Mirror (`mirror`)
 
-- `ENABLED`: **true**: Enables the mirror functionality. Set to **false** to disable all mirrors.
+- `ENABLED`: **true**: Enables the mirror functionality. Set to **false** to disable all mirrors. Pre-existing mirrors remain valid but won't be updated; may be converted to regular repo.
 - `DISABLE_NEW_PULL`: **false**: Disable the creation of **new** pull mirrors. Pre-existing mirrors remain valid. Will be ignored if `mirror.ENABLED` is `false`.
 - `DISABLE_NEW_PUSH`: **false**: Disable the creation of **new** push mirrors. Pre-existing mirrors remain valid. Will be ignored if `mirror.ENABLED` is `false`.
 - `DEFAULT_INTERVAL`: **8h**: Default interval between each check