In Star Trek: The Motion Picture, both behind the scenes and in the story, the powers that be decided that the Starfleet Uniform design from TOS (the 2260s in-universe) needed to be updated. Real-world behind the scenes reasoning was probably that the simple design of the TV uniforms wouldn't hold up on a movie screen. So the uniforms were changed to pastel colored utilitarian two-piece outfits and jumpsuits with a more 70s sensibility.
The audience's verdict? They were AWFUL.
I count myself as one of the few who not only love the TMP uniform design, but consider it my favorite and truer to Star Trek in theme and style than any other uniform design. But enough people (including the cast members themselves, who refused to wear them in Star Trek II) convinced the powers that be that the "pyjama" uniforms were in need of another, second upgrade. Enter the Star Trek Movie Proper uniforms, which this time paired a crimson jacket over a division-colored turtleneck with black trousers, AKA the "Monster Maroons" as they came to be known among certain fan circles.
All this is well known today, but here's the point of my post: IN-UNIVERSE, when were the pyjama uniforms of TMP replaced by the Monster Maroons? Specifically, what year? Head canon is required in this instance, as no canon source depicts the switch (although the earliest chronological appearance of the Monster Maroons is 2278, when the Soyuz-class USS Bozeman disappears, only to reappear nearly 90 years later during the events of Star Trek: The Next Generation) and the era in which the change was made is woefully under-explored. So basically the question is, when do YOU think Captain Kirk and the crew of the Refit Enterprise NCC-1701 said "To hell with it, we need new uniforms, we can't even sit in these damn things"?
The audience's verdict? They were AWFUL.
I count myself as one of the few who not only love the TMP uniform design, but consider it my favorite and truer to Star Trek in theme and style than any other uniform design. But enough people (including the cast members themselves, who refused to wear them in Star Trek II) convinced the powers that be that the "pyjama" uniforms were in need of another, second upgrade. Enter the Star Trek Movie Proper uniforms, which this time paired a crimson jacket over a division-colored turtleneck with black trousers, AKA the "Monster Maroons" as they came to be known among certain fan circles.
All this is well known today, but here's the point of my post: IN-UNIVERSE, when were the pyjama uniforms of TMP replaced by the Monster Maroons? Specifically, what year? Head canon is required in this instance, as no canon source depicts the switch (although the earliest chronological appearance of the Monster Maroons is 2278, when the Soyuz-class USS Bozeman disappears, only to reappear nearly 90 years later during the events of Star Trek: The Next Generation) and the era in which the change was made is woefully under-explored. So basically the question is, when do YOU think Captain Kirk and the crew of the Refit Enterprise NCC-1701 said "To hell with it, we need new uniforms, we can't even sit in these damn things"?