Hello, I'm trying to understand what are the right steps to safely update my multuserver setup from v3.1.1 to v3.1.13p1. I have read that it can be done this way: But I have also read somewhere that if you modify for example postfix config files, then you need to do something special for the upgrade scripts to preserve these changes. In my case many files have been modified, so I'm not sure what to do now. Here is my setup: How do I update it safely so that my modifications are not lost? Thank you.