Been to many a concert at Blossom when I used to live in OH. The walk from the parking lot to the venue is about a mile! They crack down hard on open container so keep it out of sight. Wish I was headed there with you but I 'll see EC in Hartford in September. Now that parking lot is close, insane and no worries with the adult beverages! Enjoy.
I saw the bus in Sylvania, too! Definitely said Church Choir. Blaring EC music and had a nice little pop out tent. Looked legit.
Did the trailer say "Church Choir" or did the people have signs?
I have never seen an offical Church Choir trailer (although it's a very cool idea and we have discussed a Church Bus LOL).
If it was Church Choir "people", then you don't need to do anything - just go introduce yourself and join the party ... we are a friendly bunch and like meeting other Choir members :)