I just speak from my observations. I fall into the group who was adult and alive in 1975. I remember how 7,000 years was hammered into us. There was never an article or a talk saying, 7,000 years has been replaced with "thousands of years." They just stopped mentioning it I think 1/1/87 WT p.30 was the last real mention; if not it was close to that time.
In fact, I think my first post on JWD was about this subject. An older brother had given an answer at the book study (2001-Creator book) and was sharply corrected by the conductor who had only been baptized for ten years, about 4 years after the last mention of a 7,000 year creative day. The conductor didn't even know that it had been taught. After all, most JWs have a hard enough time keeping up with "present truth" let alone the past.
On the WT-CD, the last mention seems to be 1/1/87 p. 30
If I remember correctly, both vaccinations and organ transplants did have an article explaining the change. I'm not sure of aluminum because my records don't go back far enough. But there are JWs still today that won't use aluminum pots/pans or deodorant or aluminum foil.
I found this item in 1982 and 1983 Awake which shows that the WTS still sees aluminum as a health hazard.
*** g82 6/8 p. 30 Watching the World ***/Aluminum Overload
Toronto pharmacologist Dr. Armand Lione says that aluminum in the food we eat and in the utensils we cook with may contribute to health disorders. He claims that as little as two or three milligrams of aluminum filtering into the brain can disrupt normal functioning and contribute to a form of senility. Lione said that the average North American takes in about twenty-two milligrams daily, and most is excreted through the kidneys. However, he warns that the efficiency of the kidneys begins to decline after age thirty, so some aluminum begins to stay in the body. What are some common sources of aluminum in foods? Commercial cake mixes, pancake batters, self-rising flours and frozen doughs. These often have sodium aluminum phosphate as a leavening agent. In sulfate salts of aluminum, known as "alums," aluminum may be present in some pickled foods, such as pickled cucumbers. Aluminum cookware, especially when used to prepare and store acid foods such as tomatoes, can increase aluminum content, the doctor declares.
*** g83 2/8 pp. 30-31 Watching the World ***/More on Aluminum
Aluminum was thought to be harmless to humans until scientists recently found it in the brains of senile people and concluded it may be a cause of senility. Now the magazine Science reports that aluminum may be implicated in another degenerative-type disease, amyotrophic lateral sclerosis (ALS, or Lou Gehrig’s disease). A study of diseased brain tissue from residents of the Pacific island of Guam, who have an unusually high incidence of ALS, revealed significantly more aluminum than did brain tissue from controls. The question of whether aluminum cooking utensils are hazardous is still open, according to the scientists.
I think the only way the WTS can get rid of their past is for everyone who remembers to die.
Blondie