The seventh season of Teenage Mutant Ninja Turtles chronologically begins where Episode 142 left off. The Technodrome is still located at the bottom of the Arctic Ocean until the last episode, when it is sent back to Dimension X. However the sideseason takes place during season 4, while the Technodrome is on the Volcanic Asteroid in Dimension X. These episodes were produced before Season 4 and aired in 1993 on the USA Cartoon Express. Wikipedia