I am currently a postdoc but I will have a faculty appointment before the proposed start of the project, am I eligible?

Applicants must have a faculty appointment (or equivalent at a research institute) at the time the award is made.  So, if the award is scheduled to be awarded for 3/1/20, your appointment would have to be effective before that date.  In addition, the faculty appointment must already be in process at the time that you apply.