ESPhttpUpdate.updateSpiffs not working

[PsY4]

Hi,
For info, i'm using STAGING 2.1.0-rc1 on NodeMCU 1.0 4M (1M SPIFFS), and everything is ok using
ESPhttpUpdate.update, but can't get updateSpiffs to work... I simply can't get the httpUpdateSPIFFS example to work, i always got the same error :

Verify bin header failed

After enabling DEBUG_ESP_HTTP_UPDATE i got advanced error :

[httpUpdate] magic header not starts with 0xE9

And that's right, spiffs.bin files generated with ESP8266FS-0.2.0 actually begin with 0x00 ...and they flash well using the ESP8266 Sketch Data Upload menu ! 0xE9 is only present in Flash bin files, not in SPIFFS bin files...

I finally removed the magic byte test , the update process can complete :

[httpUpdate] Update ok

Am i wrong ? Anybody actually managed to use ESPhttpUpdate.updateSpiffs successfully ?