Orkney Image Library [which gives a transcribed date of 24 April 1927 for the unveiling- which does not seem to correspond with the hand annotated date on the image] https://photos.orkneycommunities.co.uk/picture/number27464.asp

Orkney Herald, and Weekly Advertiser and Gazette for the Orkney & Zetland Islands - Wednesday 20 July 1921 SHAPINSAY - WAR MEMORIAL (Wreath laid on the Shapinsay War Memorial)- NOTE the same report is in the Orcadian newspaper (which is not on line) dated 21 July 1921

Orkney Herald, and Weekly Advertiser and Gazette for the Orkney & Zetland Islands - Wednesday 21 December 1921 SHAPINSAY WAR MEMORIAL-The final meeting of the War Memorial Committee took place at Elwickbank on Tuesday evening last week.

Orkney Herald, and Weekly Advertiser and Gazette for the Orkney & Zetland Islands - Tuesday 18 November 1947 SHAPINSAY WAR MEMORIAL PLAQUE [sic]

CANMORE [which cites oral evidence of 24 April 1921 being the unveiling date] -  http://canmore.org.uk/site/339101