Presumably filmed in August when the pro dancers do all the prep for the group dances.
Haha! I'm glad I spotted this post - it was on August 23rd (that sweltering Sunday) - we watched scenes being filmed firstly on a picnic table opposite the Dutch barn, and then by the bandstand as the sun was going down. There were many many retakes partly due to hazards such as Kevin skidding on the popcorn that had fallen out of his hair (no doubt this'll make sense in the context of the programme

), being chased by wasps and having to jump cleanly up on to the table!
Looking forward to Saturday's Strictly! In the meantime, here's another long distance photo (the right way up this time

)...[
attachment=3788]
The executive producer used to live round here.