Looks like you imported OLD SSL data from your backup and overwrited the new .pem created with the new install of v0.40 … Try:
- rename the current .pem
- rename the OLD certificates if imported/ overwrited, too
- Run the code for upgrading to 0.40 again
@just4t thanks for the input but well im far beyond v0.40 and i just nuked the ssl directory
A noob like i would need the steps more detailed 
I now have something to do and close for now - will try to do it again with possible new input in around 3 or 4h
I will send u and @alento my little tutorial with commands how i did it (just with already the LE reissue included) for now and later rerun all with the LE reissue as 7a) from it if everything works fine i will inform u that it can be released as workaround