Believe it or not, you can't always tell from stated web site policies. A couple of years ago ScubaBoard had one of those threads about overfilling tanks. Two different people sent a link to a PDF article about the dangers of overfilling, even overfilling a little while hot so that it will cool to a proper fill. The links were to a shop that fills a whole lot of tanks, and the indication on that part of the shop web site was that they do not even overfill to let it cool to the identified service pressure. That link was certainly a surprise to me. I had used that shop for years. I knew that it routinely overfilled LP steel tanks to a cooled pressure of 3,000 PSI, going over it while warm first. I had gotten my Advanced Gas Blender certification there, and I knew that was not their actual policy at all. I wondered if they even knew that information was on their web site. (I don't think it is there now--they have redesigned their site.)
You might also sometimes run into an employee who has received proper training on the rules but has misremembered those rules. I did a lot of diving in Florida with a particular dive shop this winter, and for several days I acted as an instructor for some friends. They were diving AL 80s, and every day they dived they were filled well over 3,000 PSI, which a lot of shops won't do. The irony is that I had to talk them into filling my LP 85s past 2400, even though the + sign indicates the rated pressure is 2640. When I explained that to the person filling the tanks, I got a "ooops! That's right!" look and a top off. I finally even talked them into a 3,000 PSI, which came after they talked with the higher ups in the shop and learned that it was OK. (If I drove a few hours north to cave country, almost anyone there would fill those same tanks to 4,000 PSI.)
You might also sometimes run into an employee who has received proper training on the rules but has misremembered those rules. I did a lot of diving in Florida with a particular dive shop this winter, and for several days I acted as an instructor for some friends. They were diving AL 80s, and every day they dived they were filled well over 3,000 PSI, which a lot of shops won't do. The irony is that I had to talk them into filling my LP 85s past 2400, even though the + sign indicates the rated pressure is 2640. When I explained that to the person filling the tanks, I got a "ooops! That's right!" look and a top off. I finally even talked them into a 3,000 PSI, which came after they talked with the higher ups in the shop and learned that it was OK. (If I drove a few hours north to cave country, almost anyone there would fill those same tanks to 4,000 PSI.)