As already indicated, this was more of a user error and not intentionally. As I was past 38 exp. and could still cock the shutter I got a hot flash and was pretty sure that the whole roll and all shots I took the last 2-3 hrs were messed up. So I rewound the film and after maybe 8 shots the film locked out of the spool.... After development my assumption was confirmed.
I used a rapidwinder for the first time and it didn't engage properly with the camera. These two shots are the only ones that are still somewhat interesting, not totally overexposed - in a light sense and in a motive sense.
I bought the rapidwinder used and it didn't come with instructions. I got them already from Tom and I'll be careful how to attach the winder properly and make sure it winds the film. Weird though that it can happen that the shutter gets cocked but the film not transported.