I know from my personal experience that once you get the CE-34878-0 the game will become unstable and random stuff will stuff will start happening: loosing items, part of bases disappearing, items growing into your base, etc. The only thing I know that fixed the problem is deleting your game data and starting from beginning, but that has always been a temporary fix and at some point you will get the error message again and you will be stuck in an re-occurring cycle. I have given up after it happen to me 4 times, which in each case I deleted the game data files and started over. With each new start I went smaller base wise and having a smaller number of thralls, which still did stop the issue from happening.
The last previous 3 times I tired deleting the data files and restoring from a backup ( I did not know about backup files the 1st time), but I still had issues even with using the backup data files with sometimes the loading screen being stuck on the loading screen on the start the gaming or exiting. I still believe that is has something to do with the auto-save function timing out that cause the error message. I am going to wait for next wave of updates and then I will try a backup file after updating the game. I have never had this types of problems with Madden or any of my other games on PS4. The tech in me wish there was a why that I could access the logs files to see exactly what is happening right before the game crashes.
I think I am going to try another combat type game while I wait for Conan Exiles pet system update.