Should I change the tracker code on every new command or search message change?

No, you don't have to change the tracking code at all. Our goal is to have a unique, persistent tracking code and all the changes to be performed with JavaScript internal methods and APIs. We use CDN invalidation when you set new commands or change something in your settings. That means that every user of your website should get a new copy of your instructions as fast as possible. In PRO trackers, changes are taking place in 1 to 10 minutes, spread around the world.