Direct from the Airbus manual
The Solid State Cockpit Voice Recorder (SSCVR) is designed to record crew conversations and communications into memory block unit in flight and on ground, when at least one engine is running or up to five minutes after the last engine is shut down irrespective of which engine is shut down first. The system can also operate in manual mode on the ground. The recorder is a four-track system and all tracks are recorded simultaneously.
The SSCVR provides storage for 2 hours of consecutive recording for each of the four audio input channels.
When the memory block unit is fully recorded, the system progressively erases recordings made in the previous 2 hours and simultaneously records new information; thus only information recorded in the last 2 hours of operation is retained. The recorded information can be intentionally erased when the aircraft is on the ground with the parking brake on, locked and electrically powered. Bulk erasure is also possible during manual operation of the system.
Recording of conversations and communications must comply with standards specified by the CAA (Ref. ATA 23-51, Audio Management, para. CAA Recording Function).
So last 2 hours is what we have
