Well, I moved fast and RTH was not activated, as I was in full control of the drone. Maybe serious RF interferences, I was in the center of Bucharest, over the Romanian Athenaeum, never tried to film in that location before, so I cannot compare with a previous situation.
Also the aircraft reconnected with the app after around 10 or 15 seconds.
What's interesting is that this happened on the second flight and on the first one, in the same location, same altitude, as I was trying to make a good panorama, nothing happened...
I think it is something connected with the custom/auto settings on video channels, as this was the first time I used custom and some other users complained that they experienced the same problem with the new firmware/iOS app, while running on custom video channel settings.