This is an interesting thing to answer…
The time period of the albums took place in the time they were made.
For example, the album "The Black Island". It was made between 1937-1938, so, the story happend in this period, and the same to the other albums. But there are some albums they were re-published and some things had to be remade, like the model of the cars and etc.
Now, about the movie: The three albums that compose the movie were made between 1940-1943, so, we can suppose that the story happened in this time.
About the Interpol thing, according to my researches (I’m feeling a detective now HAHAHA), the first time the name Interpol was used, was in 1946. So, we can suppose the movie happened in this period until 1950, or perhaps later. This is what I think about the movie :)
Hope it helps! =D