Thanks, appreciate it!
Well my first major Upgrade was from Laravel 4 to Laravel 5 for my clan site and was pretty straightforward. It took some hours in order to get back all working again but these changes were trivial but had to be made in all my controllers for example.
Recently I upgraded my personal web page andreas-wiedel.de from Laravel 5.1 to 5.2, later on to 5.3 and not long ago to 5.4, which was really easy.
The Laravel documentation told me every time what has changed and what had to be adjusted in my code.
I recommend to always check the github project for laravel/laravel (https://github.com/laravel/laravel) and compare your code with it because of added features like the TrimStrings middleware which has been added to the HTTP kernel in v5.4.