When a user submits time and expense entries, the Submit dialog appears where they can specify who they want the entries to be submitted to. Who are the entries submitted to when the approver is not yet set in Core, say Client Manager, Employee Manager, etc.?
You have the option to submit time and expenses to a specific user, Project Manager, Client Manager or My Manager in the Submit dialog. In case you submit to a specific user, you can choose who you submit to from the drop-down list. The Project Manager is required for every project profile and so this role is always set. If you select Client Manager or My Manager, but do not have these roles set, the entries are submitted to the Project Manager by default.
Sometimes the submit options are disabled for you due to security permissions. In that case, when you choose to submit, no dialog appears and the entries are submitted to the user specified under Submit To in Employees > General > Rates & Options. In case that role is not set, the entries are submitted to the Project Manager.