The Sentimental Journey TV series is based on Sentimental Graffiti,
with the same 12 main characters and same background history.
However, there are some minor changes that conflict with some of
the other stories in Sentimental Graffiti.
The stories seem to be "parallel world" type stories.
The stories in the TV series take place before the girls send the
letter to the "boy".
The broadcast schedule of Sentimental Journey was as follows.
(channel 12, in Tokyo)