I mentioned it in first post "Factory settings exc. EU-->US". Lets see, next time I will test EU settingsWhat? You're just mentioning now that you're using STunlocker?
You do realise the motor uses more battery when motor assistance no longer stops at 15mph? and ANY climbing above 15mph uses tons more battery. This combined with a super draggy rear tyre is probably contributing far more to your range issues than you realise.
Stick a fast rolling rear tyre on, inflate it to 30psi and reset your settings to limit it to 15mph and then do a similar ride.
Shimano Steps batteries are rated to retain at least 60% of their original battery capacity after 1,000 charging cycles (pretty much impossible to manage within the 2 year warranty period). so yours if showing 83% you're wasting your time trying to get it warrantied.