You sound as though you know that for sure, so I've used my Sherlock Holmes-like powers of deduction to determine which of those dates is the most likely. This was their itinerary:
June 6 Nashville, Tennessee June 7 free/travelling June 8 free/travelling June 9 New Orleans, Louisiana June 10 San Antonio, Texas June 11 free/travelling June 12 Des Moines, Iowa
Now, Little Rock, Arkansas, is only a small detour on the route from Nashville to New Orleans (stay on Highway 40 instead of turning left onto Highway 55). Likewise, Little Rock is only a small detour on the route from San Antonio to Des Moines (Highway 35, then turn right onto Highway 30). Small, that is, in American and Australian terms. It'd be a massive detour for we Brits!
However, the distance from San Antonio to Des Moines is about twice as far as from Nashville to New Orleans, and they only had a day to do it. They had two days to travel the shorter distance so logically it was then that they had more time to stop off in Little Rock, hometown of Bill Clinton, no less.
I'm unsure which date it was but I originally deduced it was the 8th as well, seeing as the band would most likely want to spend the 7th in Nashville, get to Little Rock on the 8th, depart in the evening, get to New Orleans where the pictures show them staying in a hotel and spending the day of the 9th seeing the town before the show that night.
This led to the SpotlightON facebook link that you posted, where I scrolled to the bottom and it said it was the 11th. I then clicked on the SpotlightON website where it had stated that they stopped between their dates in Nashville and New Orleans....so, there are conflicting accounts.
In the pictures they can be seen taking their time, eating lunch, hanging out by the river, just relaxing, without a sense of urgency while they are in Little Rock, but this doesn't mean anything. They could have done this on the 11th as well and still had plenty of time to make it to Des Moines for the show the next night. Although, I do think it makes more sense that it would be the 8th.
The woman from the SpotlightON facebook page, her name is Catherine Nelson McKinnis. I messaged her about the date in Little Rock and she said it was June 11.
The pictures from the 8th and or 9th are New Orleans, where you see them sitting in the hotel, and the one they are walking around in the street, and the one where Brendan is seen being punched from behind. ;D