Added my (late) vote for within 1 month
My first bike (04 ninjette) was just at the 1 month mark when I felt I was a better rider than I am. Drop wasn't that bad, but did enough damage I knew I couldn't easily fix.
So I sold it to dealer and got a brand new 11 ninjette instead.
That bike is 3 weeks old today, has 550 miles and never been dropped (hoping to keep it that way).
However I remind myself every single corner, no matter sharpness of turn or my current speed..."you are not a motoGP rider" and I end up taking corners probably too slow... but I'm on 2 wheels and the bike is still working & pretty, so I'm good w that