I can confirm that in Liberty Converse the maximum data retention policy is 730 days.
The default is set to 456 days and after this data is deleted completely from the system, and no access to this data would be obtainable from Netcall.
If data retention is required what I would suggest is saving the Interactions report data either monthly or at the most every 3 months to a network store.
Note that Call Recordings are only stored for 90 days, if you need to obtain call recordings for longer I would suggest setting up an archiving script to copy the call recordings from the Liberty system to a network data store. Call Recordings can easily be found outside of the Contact Centre Interactions report using the Call ID which is stored in the Interactions Report. Using the Saved Interaction report and an archiving policy for call recordings that should enable you to store information for as long as you require.
I have also been advised that we do intend to allow more control over data retention including call recording retention in a future release of Liberty Converse early next year