It is possible to generate a flat netlist after running Calibre -lvs -hier.
You must use MASK SVDB DIRECTORY option CCI during the database extraction and then use Calibre Query Server to do the rest.
Note: This process requires licenses to run both Calibre Query Server (calibreqdb or caldrclvseve) and Calibre CI (Connectivity Interface - calibreci).
Invoke Calibre Query Server:
% calibre -query svdb
After getting "OK: Ready to serve." prompt, enter the remaining commands (in bold):
INITIATING HDB QUERY SERVER:
OK: Ready to serve.
LAYOUT NETLIST HIERARCHY FLAT
LAYOUT NETLIST WRITE flat.net
The resulting flat.net file represents the flat netlist.
Additional information for the Query Server commands can be found in the Calibre® Query Server Manual while the licensing information can be found in the Calibre® Administrator's Guide.