ACARS AP Disconnect
Usually crew initiated AP disconnect is not reported either by ACARS or on the PFR
The message is generated by an unusual AP disconnect either by the AP sys (Auto) or by the Crew using the FCU (Non-Normal Method)
The message is present to alert maintenance that perhaps the crews sidestick disconnects are not functional & they needed another (manual) method of AP disconnect or that the AP disconnected for a variety of reasons