Tilaa can move your VPS's from one physical host to another while it's running. This is called a "Live migration" and has no impact on the availability of your server.
Altho, while a VPS is being migrated, the tasks will be unavailable. You can choose to cancel the migration if you need to use the tasks on our dashboard.
We do those migrations to evenly distribute the load on our platform or to empty a physical host when we have to perform maintenance on it.