diff --git a/README.md b/README.md
index cad1693..60b168c 100644
--- a/README.md
+++ b/README.md
@@ -26,7 +26,7 @@ Run `python uniflash.py -h` to see all parameters. But there are several typical
 
 ### SC6531E
 
-This is the default target for UniFlash, FDLs for it are shipped in the repo and you don't need to configure anything else.
+This is the default target for UniFlash, FDLs for it are shipped in the repo and you don't need to configure anything else unless your model requires signed FDLs.
 
 For SC6531E, firmware is usually 4MB long, so you just need to run `python uniflash.py dump your-output-file.bin` to dump the firmware image and `python uniflash.py flash your-input-file.bin` to flash it.