What a simple DIY solution! I'm tearing my hair out - how I couldn't think of it myself! 🙂
My first assumption was I miss some kind of hidden Zorro feature in the docs.
Thank you for the hint!

But in my case NEWDAY in a strange way was firing on every bar.
Code
if(NEWDAY) printf("\nIt's new day!");

I don’t know if this is a bug or a feature…
But
Code
if(at(1010))  printf("\nIt's new day!");
Do the trick!