To get the new firmware version to show up, you simply need to reload the matter-server integration.
Note: Make sure that the firmware update process is not taking place on any other switches as this may interrupt that process.
Go to "Settings" > "Devices and Services". Then, on the integrations tab, find "Matter (BETA)" and click on it to get to a screen like below.
Click on the three dot drop down menu as shown above and select "Reload".