Any Unknown or Unlisted Aircraft Manufacturer
Flight Crew Commercial; Flight Crew Private
Workload; Physiological - Other; Situational Awareness; Troubleshooting; Confusion; Communication Breakdown
ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR
Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented
Chart Or Publication; Environment - Non Weather Related; Human Factors
While flying Southbound at 1;800 feet. I established radio communications via CTAF. Self-announcing to low level helicopter traffic in the vicinity of the [POU] airport in order to ensure proper separation. I was queried by a voice as to my call sign; in which I replied my call sign. I believed at the time that I was speaking with the operator of the helicopter which I was attempting to communicate with. The voice then advised me that POU Tower was currently open. I requested clearance; which was approved. The Controller did advise me that a violation may have occurred. The flight continued without incident where we landed safely at the destination. All NOTAMs for the enroute phase of flight were checked prior to with no mention of normal hours resuming at POU. It has been my experience since the COVID Pandemic that Dutchess Tower was operating on an amended schedule; 4:00 PM Tower closure. I was not aware nor did I see any notice that normal hours had resumed. I did call the POU Tower after landing. I did identify myself as the pilot. ATC collected my information and advised me [further]. I was advised that no notice or NOTAM was put out as to the change; but LACK of a NOTAM was the indication that normal hours had resumed.A NOTAM or notice needs to be circulated advising local pilots who have become programmed to the early Tower closure since the beginning of the pandemic; that normal hours have resumed. More so than just the 'lack of a NOTAM.'
Pilot reported the ATC Tower at POU airport closed mid-afternoon during the COVID-19 pandemic; but unbeknownst to the reporter; the Tower had returned to normal hours of operation during this flight.  Reportedly; there was no notice or NOTAM advising of the change.