There are a lot of distractions because of pre-Christmas trading. I have to help my wife.
But here's the important part: I reworked and debugged the timer. Until now, it counted a simplified calendar with 30 days in every month and no leap years, while the engine's automatic calculations use the real calendar. That caused a discrepancy. So I reworked the server timer. It may not sound difficult, but there are many details, including updating the database. So there it is.
I've almost worked out how to record and process ship-flight data on the server. I had a general idea of what was needed, but the details turned out to be quite complex. Nothing insoluble, but there are a lot of different parameters and logic. My head is spinning. I need a few genuinely quiet days to get through it.