Over how many months/days/weeks is the full story of Sweeney Todd supposed to take place?

In the play Johanna sings something about Anthony marrying her (after he breaks her free from theasylum) and she says "...that was last August." which makes me think that the play is supposed to take place over a few months, I'd kinda like to know exactly how many months or weeks. I know in the movie the story takes place over a week or so.