Welcome back! You might want to wait for the new release, which is imminent.
As for the date/time readout, the new system which you see is based on in-game hours: the number on the right of the / sign is the number of in game hours in a month, and that on the left is the number so far elapsed in the current month.
In game hours are used for the measurement of speed and journey times, so the new display is important if one is setting up interlocking services/quasi timetables, for example.