Filter Employees and post the start of an attendance with a project

Hi,

we are currently trying out your API and noticed:

filtering the employees with a custom attribute is not possible
its not possible or documented how to retrieve projects
its not possible or documented how to create an attendance without a end_time and a project_id - although that's what the UI is doing

I've read that some of these things are in discussion for a new API version - can you give us a rough estimation if and when we can anticipate this?

Thanks in advance and have a great day :-)