Piano Forum

It really depends on... well, everything.
If you're playing pieces at level 7 and up and you spend a lot of time on it, I think you'd be capable of pulling it off within the month.  It also helps if you've played some faster and virtuosic pieces before like Bach Inventions or Mozart/Beethoven sonatas.
The most difficult part of the piece for me is getting it up to tempo. The performance tempo is really, really fast! The piece is supposed to last close to a minute and a half. Hence it is commonly referred to as the "Minute Waltz."
Took me about two weeks to get the notes down and another week to get it up to tempo, though I haven't quite taken the time to perfect it yet.
It also doesn't hurt to practice some Hanon Exercises or something while learning it.
Hope this helps!

Ryan