I imagine they did as last year where evevryone had to go out of Longleat the same way.
No - just from the "Blue" Car Parks there were (at least) 2 separate lanes out... However, the second did not open until ~1745 since there were still cars coming in on one of them...
We stayed for the prize giving etc to avoid the mad rush. Left ~1745 and took 15 mins to get out