Dann fehlt doch nicht mehr viel, geht automatisch weiter,so sah es bei mir aus.
If there is no "Sending file: /ota/image_arduino.bin" log entry, ensure all firewalls have been COMPLETELY disabled on your system.
......200 GET /ota/image_arduino.bin (192.168.4.1) 14471.97ms
..........Current IPs: []
No longer on "FinalStage" SSID, all done! Now connect to the sonoff-#### SSID and configure for your WiFi (it will not be configured).
Quitting.