>Which possibilities do we have to agree otherwise?
How we handle this at GrantTree is with the following logic: you can always leave the company at any time by giving your contractual notice (generally 4 weeks). If you can do that for all your roles, it seems illogical that you couldn't do that for some of your roles. So our agreement (in the form of a policy) is that you can leave any role by giving 4 weeks notice.