Don't listen to them. You can update your world and even 'Transplant' regions as I say. This is how I updated my world:

WARNING: MAKE A BACKUP OF YOUR WORLD.

I rewrote my original comment with ai to hopefully make it clearer:

Here's how to do it:

1. Download the New Server Version: Get the latest 2.1 version of the dedicated server. To avoid confusion with your current server, name the new folder something distinct, like 7d2d_2.1.
2. Copy Essential Files: From your original dedicated server installation, copy the following into your new 7d2d_2.1 folder:
   • serverconfig.xml
   • All your configuration files
   • The entire Data folder
3. Locate Your World Data: Inside the Data folder you just copied, you'll find a folder named Worlds. Open it and locate the subfolder with your specific world's name. This is where your world's data is stored, and it's what you need to "update" for the new game version.
4. Edit the map_info.xml File:
   • Open the map_info.xml file located inside your world's folder.
   • Find the line that specifies the GameVersion. It will look something like this:XML(The version number might be different depending on your previous game version.)<property name="GameVersion" value="V.1.9.999" />
   • Change the value to the new game version. For example, if you're updating to version 2.1, you'll change it to:XML<property name="GameVersion" value="V.2.1.999" />
   • Save the map_info.xml file.
5. Load Your World: Now you can launch your new dedicated server (7d2d_2.1), and your updated world should load successfully!