It was the second lowest in the region in 2014 at 31.7% - 55.4% this year is the highest by far. Seems odd.
That is a bit odd. I think the Local by election with 4 candidates on the biggest island was the factor. About 1300 of 1750 electorate of the Islands live on St Mary’s and having 4 candidates for the by election there led to quite a large likelihood of an elector knowing at least 1 candidate.