To see what versions of Meza are available, do:
sudo meza update
This will list available versions. You can then select one of those versions to update to by doing:
sudo meza update <version>
You can also update to the most recent version of a branch. For example, the
31.x branch is where all
31.x.y versions exist. By doing
sudo meza update 31.x you'll be at the latest 31.x version.