OK, let me try this again:
FACT: JWs teach that "day" seven can be used to infer the approximate length of the other six creative "days".
FACT: JWs teach that "day" seven is 7000 years long (or something every close to that). They refer to this length of time, correctly, as being "thousands" of years.
FACT: JWs teach that each of the six creative "days" was "thousands" of years long. Based on the understanding of "thousands", noted above, these "days" were probably somehting like 7000 years each, or perhaps a bit longer.
FACT: JWs never describe the six creative "days" (or even the entire creative period) as being billions of years, millions of years, hundreds of thousands of years, or tens of thousands of years long. They do, however, use these expressions to describe the age of the universe and "formless" Earth.
FACT: "Billions of years" and "millions of years" are frequently used to describe the "false" teachings of science: evolution, geologic time scale, geologic column, etc...
CONCLUSION: JWs actually teach that each creative "day" was something like 7000 years long.