It's difficult to answer this question because the term "depot" as used here is very generic. Depots are typically facilities for centralized storage or transportation hubs. If the "depot" is a contractor facility (contractor-owned, contractor-operated) and the contractor wants to propose on an Air Force requirement, then I don't see an issue. If the depot is government-owned, contractor-operated (GOCO), the contracting officer will have to make an adjustment to a competitive proposal to eliminate an unfair competitive advantage an offeror would have by performing the contract in a government facility, which is government property. FAR subpart 45.1 provides guidance if this is the case.