Terasawa wrote:Jamila's memorial shows he died in 1990-something, but IIRC, there are references to the '60s being the present as well in some episodes. It's ambiguous.
The original plan was to set Ultraseven in 1987 but I don't know if that was ever confirmed by anything on screen.
Apparently TV-Kun mentions Seven takes place in 1987, but it's never stated in the show. On the other hand, in episode 43, the current date is shown as August 30, 2000, so make what of that you will.
However, there are some bits and pieces from the show that put it squarely in 1968 such as a news paper showing off the date of May 16, 1968 in episode 38.