Can a job be made unfirm once it has been firmed?

I'm having a total brain fade here. Once a job has been made firm, can it be made unfirm again? We're running E9.04.506C, and un-engineering and un-releasing does not un-gray the UnFirm button. I don't remember having this as an issue in Vantage 8, but I could be mistaken.

Ernie Lowell
Diba Industries