I was having the same trouble, that the game would crash at the end of the day, and the day would repeat when I logged back in. I tried the suggestion to avoid sending anyone on quests, but I still had my day end with error #906207. That said, I did have someone come in having just finished a quest. Maybe it would have worked if I had ignored the finished quest and refused to finish OR start quests? I’m not sure, but I’m going to come back later and see if things get better.
That said, I like the change where contributor lists aren’t automatically loaded when I click on a building in town. That always took too long to load from my end, and probably contributed to the server overload as well. Once the stability issues are addressed, I think the changes made last night will be for the better.