After exploring for diamonds and kimberlite on their Flinders Island Project ground for the past 23 years, the present joint venture partners have now decided to relinquish the licence area that they held which covered the central portion of Flinders Island. EL 6420 and its precursor licences had formerly covered ~16 square km of the island, being that portion lying inland from an encircling 200 m wide coastal land strip. For the first 18 years of tenure of the subject area, the licensees at that time undertook conventional exploration designed for locating a buried diamondiferous kimberlite. The results of making this search have previously, since November 2014, been progressively released into the public information domain by DSD acting under the provisions of the 'Sunset Clause' to the SA Mining Act and Regulations, as a set of licence annual reports held in Env 9637 that are accessible via the Department's SARIG data portal. [ Prior to this project getting underway, original private diamond explorer Stephen Cooper, with later assistance from public companies Livre Resources and Tawana Resources, had performed a first phase of exploration for diamonds across the greater ELLISTON 1:250k mapsheet area (cf. Envs 8973, 9206, 9447 and 10800, plus an article within MESA Journal 24). ] During the period since 4/1/2017, current JV project majority partner and operator Kalyan Resources did no new field work, but continued to perform desktop studies utilising the information and results that it had gained from earlier drilling programmes and surface geochemical/mineralogical sampling that it had conducted between 2014 and 2016. As previously reported, Kalyan has collected in excess of 5 tonnes of samples, including 230 surface rock, loam scrape and aircore drillhole samples, which were all processed at a heavy mineral analysis laboratory for detecting and describing any contained kimberlite indicator mineral (KIM) grains and microdiamonds. The results of this work revealed the existence of numerous KIM as well as some microdiamonds, thereby bringing to 24 the total number of diamonds recovered from Flinders Island to date. The widespread occurrence of KIM in surface loam samples and in some samples taken from drill spoils and drill core, with grain textures indicating minimal weathering and abrasion, is strongly suggestive of a local provenance for the likely kimberlite host rocks. In addition, in many instances all of the indicator minerals for an eroded kimberlite are represented within Flinders Island cover samples, which is not supportive of there being a distal source for the KIM, unless glacial activity is involved in some way. Of critical importance for target vectoring is the spatial association of the full range of indicator minerals including microdiamonds, which supports the current premise that there is a proximal primary kimberlite source for these minerals. As already mentioned, there has been a vast amount of exploration activities conducted on Flinders Island via the many drilling programs, loam and deeper cover heavy mineral sampling, besides detailed mapping and geophysical surveys: however, until recently there was a lack of regional context realised regarding the positive significance of the various results obtained. During the reporting period, Kalyan has focussed exploration attention on attempting to correlate data and interpret the extensive data set, with a view to refining the exploration targeting. No field activities were undertaken in part due to border closures, travel restrictions and quarantine requirements associated with the COVID-19 pandemic. The outcome of the desktop work has been to realise that all likely exploration targets lie outside of the bounds of EL 6420. Historic samples reporting KIM, which came from within EL 6420, are now considered to be sourced from the younger cover sediments including the Pleistocene Bridgewater Formation, which has been demonstrated to contain both KIM and microdiamonds. In addition, the beach zone heavy mineral placer strandlines in the Gem Pan area, which have been shown to contain high concentrations of KIM and some microdiamonds, do not extend into EL 6420. As a consequence, it became clear that EL 6420 probably has low prospectivity for kimberlite or derived detrital diamond accumulations.