The action takes place in 1972 but Mircea Florian's song "Cu pleoapa de argint", which they listen in the apartment, was released in 1975 as part of the album "Padure De Voie Buna".
The haircut of the 12th grade boys in the movie is wrong. Romanian schools did not allow at all long hair in 1972.
At minute 85 there is a clear shot of the street corner with architectural lighting and a street pole, both of which have appeared only 40 years later in Bucharest. Same for the cobble-stone sidewalk.