From the BBC’s own website:
11. The members of each national jury will be presented with pre-recorded sequences of a dress rehearsal of each song. They will cast their votes prior to the live performance, based on the rehearsal viewing.
That’s not right, is it?!
I contacted the BBC and this was their reply:
“The Juries will be shown a recording of the second full dress rehearsal for the Grand Final (which takes place on the Friday evening). They will give their votes based on the performance during that second dress rehearsal.”