Sure can. In fact, you can trim and prep all of your meat you just can't season/inject/marinate it.
As to the point of bringing the label, I normally don't. With my chicken, I'm picking up enough chicken for 4 comps at a shot, so it's trimmed, cryo-sucked, and frozen up to a month or so in advance. The label wouldn't tell them much.
Great advice. Can prep it all at once then just take out what you need for each event!! Thanks much for the response.
Joel