Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Situational Awareness; Distraction; Confusion; Communication Breakdown; Workload
ATC Issue All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew Requested ATC Assistance / Clarification
ATC Equipment / Nav Facility / Buildings; Airspace Structure; Human Factors; Environment - Non Weather Related
We were delayed out of ZZZ1 due to ZZZ Center being closed for a COVID. Dispatch sent us a new release with a route that took us well west of ZZZ Center's airspace. After takeoff and soon after leveling off at cruise Altitude; ZZZ1 Center asked if we wanted to stay on route or get a short cut. Our original route was [route 1]. They offered [route 2]. The Captain and I discussed the new route and accepted it. The Captain sent a message to dispatch informing him of our new route.Our discussion and thoughts were that ZZZ2 and ZZZ3 Centers must have divided up ZZZ airspace and radar coverage; and were now allowing routing through this airspace. When ZZZ2 Center was controlling us; they asked us for our ZZZZZ [waypoint] time estimate; and gave us the instruction to contact ZZZ3 Center 35 miles north of ZZZZZ. We were never told radar coverage would be lost.  When we checked in with ZZZ3 we were told we were in radar contact. Several other Company flights; as well as other airline traffic; were also flying through this 'closed' ZZZ Airspace and under the control of ZZZ2 Center.Dispatch sent us a message later in the flight asking the Captain to call upon landing. There was a question with the Dispatcher as to the legality of flying through domestic airspace without radar coverage. (Dispatch used the term 'uncontrolled' airspace.) The Captain mentioned we didn't think we were ever in uncontrolled airspace; as we were in Class A airspace.  He explained to Dispatch that we thought the centers had provided coverage throughout the flight.I am writing this in case we inadvertently flew through domestic airspace without adequate ATC control; and therefore unintentionally violated a company policy.
Air carrier First Officer reported receiving an amended clearance due to a ATC Center going ATC Zero and questioned if they had violated an FAR by flying in uncontrolled airspace.