Atheists have no idea when anything happened. When I started studying evolution, I was told the earth was 200 million years old. Next it was 800 million years old. next it was 1 billion. This was followed by speculation that it was 2.8 billion. A few months later it had increased to 3.5 billion and the last I heard from the late Christopher Hitchens is was 13.5 billion.
Where and when did you start studying evolution? On your own account, you were born in 1941. I own a book, 'Evolution and its Modern Critics' by A. Morley Davies, that was published in 1937, and that gives (pages 24 and 32) the age of the Precambrian-Cambrian boundary as about 600 million years and the age of Early Precambrian rocks as 1250 million years. Another of my books, 'General Astronomy' by Harold Spencer Jones (published in 1934), says (page 29), 'The oldest rocks whose ages have been directly determined ... are some of the Lower Pre-Cambrian rocks, whose age is found to be about 1,300 million years. It therefore seems probable that the age of the Earth (from the time when the crust formed) is of the order of two or three thousand million years.'
When I started studying science, during the late 1950s, one of my first books, which I still have, was the 'Newnes Pictorial Knowledge Atlas'; it was published shortly before the launch of the first Sputnik in October 1957, and therefore when you were in your teens. With reference to the age of the Earth, it states (page 16), 'The most recent research has made possible a precise-looking estimate: 4.55 billion years'.
From this, it appears that scientists knew before you were born that the Earth was more than a billion years old, and that the definitive age, 4.55 billion years, was established before you were 20. How, then, can you say that you were taught that the Earth was only 200 million years old and that the supposed age of the Earth increased to 3.5 billion years after you began studying evolution?