There’s no delay in that test sketch that could cause the disconnect (as said I don’t get disconnected when App is offline. It connects and stays connected then).
I also don’t write to the App at the moment just Blynk.run and 4 Blynk Read functions.
But get disconnected often once the App is open so may the App flood or isn’t that possible?
Will look into that tomorrow, didn’t know about the enabling of debug.
By now throug testing I figured out you will get a flooding warning when flooding.
But I don’t get those in my sketch so I’m not flooding the server but get disconnected regulary once Blynk app is set to run. About every 15 Seconds I guess.