Here's my bad advice:
I got there last Saturday around 11:30. Probably <10 people waiting for them to open at that point, but a lot more showed up by 12. So if you want to be near the front of the line or in/out quickly that might be the best way. I can't imagine them being as crowded as they were last week (I'm sure this is a stupid thing to say), but there were a lot of people checking it out because it was opening day.
If the line is long when you get there, and you know what you want in growlers before tasting anything, maybe fill out an order sheet and bring it to the growler station, then hop back in line for a flight/pour.
There are tables inside and outside (good if the inside is too crowded and you can grab something from the food truck, although they prefer you don't take glass outside, there are plastic outdoor glasses).