there is the export/import feature - before upgrading the mod version, sell all equipment you have and your parties, export your character, upgrade, start a new game with the same background options and import. Your character has now "returned" after a long adventure abroad to find that since he left, real estate has changed hands, you lost your old castles and most lords have forgotten about you (hard to recognize you with this silly bird). You have your skills and a good sum of money to collect your old warband and start rebuilding your old glory.