It is not possible to move away from them. nic.io is the registry for .io domains, so you can't move to anyone else. They also act as a registrar for their own

It is not possible to move away from them. nic.io is the registry for .io domains, so you can't move to anyone else. They also act as a registrar for their own TLD, so you could move to another registrar, but ultimately they're responsible for .io delegation.