During the night 4-April-2021 at 02:04 UTC an earthquake with magnitude Mw3,0 at 5,7 km depth took place 1,5 km south-west of Keilir mountain. This earthquake was felt in Reykjavík area and outside of it. Based on the earthquake location it looks like it is located in the dyke or close to it. This is part of the Krýsuvík-Trölladyngja volcano.
Along the magma dyke there seems to be forming focused points of earthquake activity. Currently I am seeing two location. The first location is around the eruption in Geldingadalir valley (former) and the second location that seems to be forming is just south of Keilir mountain. It has been my experience during the eruptions over the last few years that this type of earthquake activity might suggests that new location where eruptions might take place based on this earthquake activity. It is impossible to know if anything is going to happen. There is no change in GPS data since the eruption started. The GPS data can be viewed here.