Tracking Codes and Billable time

Would it be possible to add Tracking codes to the billable time entry form and to flow them through to billing and invoices for WIP time in the same manner as is now done for disbursements income so that the revenue from time reflects the project (tracking code) on the billable time entry?

Added to the latest version (15.0.44)

Perfect. Thank you!! Now we have a workable project billing system for both time and expenses. Awesome.