I don't understand the messages either. They are not customer-oriented (lots of things on railways in Europe aren't).
Basically there is a "normal" timetable for the train numbered ICE1600 and occasionally the timetable will be altered for a short period due to engineering works etc., however 0850 is the normal departure time from Munich, so I don't know what running 80 minutes early is supposed to mean. There were some dates where this train departed Munich at 0808, but I can't find any where it departs at 0730.
Anyway the majority of people aren't going to know or care what the "normal" time is, they only care what time it runs on the day they are travelling. Even a regular commuter wouldn't care about taking a train with the same headcode every day, they just want to get to the same place at roughly the same time every day, but perhaps the message prompts them to check the timetables.
Engineering works are usually planned months in advance so any last-minute changes are going to be because of unplanned things like floods...
Thanks for your info. Helps me understand the reason for the message anyway, if not what it means practically. Also agree it isn't very passenger-friendly.
I have flexibility in my travel schedule this day, so a nominal change of time isn't going to cause a big issue. Mainly just not sleeping in.
Appreciate everyone's patience with a newbie learning the rail stuff.