August 1st, 748

[Fantastische Hure]

…is when the series begins.

1. Bulma said Bulma is on summer-break. Summer-Break in Japan ends end of August I think.
2. Says has 30 days left at the very beginning so most likely beginning of month.
3. When August is over, Goku goes to train with Kame-sen’nin in September. September to May is 8 months.

It all falls into place.

 

[Warmmedown]

Was she in high school or university?

 

[Fantastische Hure]

In chapter 69 Bulma said she decided to leave school early (for the day), because it was boring lol. I assume high-school because she was 16, but who knows.