If you got latest 1.4.3 and you played on 1.3.1 before , there are different story routes in new version.questin : do i have to start the the new game or just continue the old 1.3.1 , else do i miss any thing if i choose to continue ?
And i am not sure about this one , but maybe there are some new missable or random events that won't trigger after main story and big adventure in save from old version.
Just start new game , and choose a different story route , and experience all new random events instead of loading save from old version that might block some events.