The original post in this thread was made about a year ago, and I did not notice it for a long time. I was not back in Florida until a few weeks ago, and when I went in to Force E, I asked them about their fill policy without mentioning this thread. They said they would not fill an aluminum tank made before 1989 (31 years ago). They said steel tanks had no limits. I then told them about this thread, and the people there were dumbfounded--they had never had such a policy. I also told Ana, who was also dumbfounded, and I am sure she was not making it up.
So something happened with some employee who clearly misunderstood something. That shop will fill steel tanks of any age, assuming they have had the standard inspections.