Watson (W J Watson 1926) suggests that the probably 7th century. St Flannan of Cell da Lua may have been the saint of the Flannan Isles, and Nisbet and Gailey (H C Nisbet and R A Gailey 1960) compare the oratory to that on Rona (HW83SW 1) which they date to the 7th or 8th, centuries by analogy with the Irish oratories eg. Skellig Michael.
The Flannan Isles Lighthouse remained as a manned Station, reliefs and water supplies being carried out by the MV POLE STAR from Stromness until 28 September 1971. It was then demanned, and became a Major Automatic Light. Today the Flannans receives an annual inspection and maintenance visit from the boards Tender NLV PHAROS. Flannan Isle.