Google maps turn by turn and virtual dashboard bug?

So when I'm using Google maps for directions I might occasionally get the first direction appear on the virtual dashboard and that's it, I never expected any more as I believed it wasn't a feature.

However recently I was using Google maps and I had turned off the car with the stop start button, didn't turn off the infotainment.

When I restarted I noticed I was getting turn by turn with distance countdown, diagrams of upcoming junctions, road names, basically all the details from Google maps appeared in my virtual dashboard until the end of my journey.

I tried this a few more times and it worked all but once when they stopped after a few minutes.

Anyone know what that's all about?

My hardware version is H56, software 1985.