Commercial Fixed Wing
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 97; Flight Crew Type 14972
Situational Awareness; Distraction; Confusion; Workload
ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Procedure; Environment - Non Weather Related; Human Factors; Airspace Structure; ATC Equipment / Nav Facility / Buildings
We were delayed out of ZZZ1 [airport] due to ZZZ Center being closed for a 'COVID cleanup.' Dispatch sent us a new release with a route that took us well west of ZZZ Center's airspace. Following takeoff and soon after leveling off at cruise altitude; ZZZ1 Center asked if we wanted to stay on that route; or get a short cut. They offered: Route Y (Original: Route X). The FO and I discussed the short cut; and I sent a message to Dispatch indicating we were going to accept this new route.Our thought was ZZZ2 and ZZZ3 Centers had divided up ZZZ [Center] airspace and were providing radar coverage for this route; though it appeared that normal radio coverage would be lost north of ZZZZZ [Waypoint]. We were instructed to contact ZZZ3 Center 35 miles north of ZZZZZ. We were indeed asked for an ETA for ZZZZZ; but we were never told radar coverage would be lost. When we checked in with ZZZ3 [Center]; we were told we were in radar contact.Dispatch sent a message later in the flight to call upon landing. There was a question as to the legality of flying through 'domestic' airspace without radar coverage. (Dispatch used the term 'uncontrolled' airspace.) I explained I was unaware we had entered 'uncontrolled' airspace since we were in Class A airspace. I explained; I thought the centers had provided coverage through the route; but we had an area where radio contact on regular frequencies was lost.I am writing this in case we inadvertently entered domestic airspace without adequate ATC control and unintentionally violated a company policy.
Air carrier Captain reported not knowing if they were legal to fly in domestic Class A airspace in an uncontrolled environment after a Center had gone ATC zero.