Approximately what was the date of the trial in Chapter 20 of To Kill a Mockingbird?

Although there is no specific date given for the Tom Robinson trial in Harper Lee's novel, To Kill a Mockingbird, we do finally learn the exact year in which the story takes place. There are other references to historical events which determines that it is definitely the early- to mid-1930s, but Atticus specifically tells us the year during his summation to the jury.

"There is a tendency in this year of grace, 1935..."

We also know that it is probably July or August, since Atticus relates that he has received an extension until "summer" and that Jem and Scout are out of school. Shortly after the end of school, Scout receives a letter from Dill saying he will not be coming to Maycomb since "he had a new father." Then,

... the state legislature was called into emergency session and Atticus left us for two weeks.

Atticus returns, and Dill makes a surprise visit. "We had a week of peace together," Scout tells us. Then, on Sunday, the day before the trial, Atticus makes his stand at the jail before the lynch mob. So, assuming that school in Alabama lets out in early- to mid-June, by adding the two weeks that Atticus was absent plus the "week of peace" and several days in between, this places the trial no sooner than early July 1935. It, of course, could be as late as August.