As in you have authed and just used the machine, its then just forgotten who you are?
There is a timeout, however it is not for AD accounts, purely USO. I'd be keen to see whats happening here from your end.
That should not matter, essentially all we do is accept username you send and add it to the IP address you are coming from in the database.
Ideally, I'd need a support case, as you can hopefully understand I need to account for my working etc, I am more than happy to look into it further with you but from a support perspective, I can only do so much here before I cross the line