In the early days of autos there were a few auto strains that would be done in sixty days or less. Sour 60 is one of them. I have an old auto line that can be done in 60, if using a small container. They seem to go fast when roots hit bottom. And if pollinated early, they can get done faster, too. But they were small. I had a giant one that was 18 inches tall. Most were much smaller.