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Much of the major flare (strong C, M, and 1 X) activity we've seen recently has occurred near the east limb or west limb of the Sun. They seem to be occurring more often than would be expected if the flare locations were randomly distributed. After a bit of research, I found two phenomenon, the Active Longitude, and a 24-day period between major flares, that could explain why we're seeing so many flares recently concentrated near the limbs. Or more precisely, not to explain why they are occurring near the limbs, but to explain why they are occurring in the same place so frequently. I would suggest that we have been in a phase where the Active Longitude from the earth view happens to be near a limb (and a subordinate Active Longitude perhaps 180° from the primary Active Longitude at the other limb). However, since the latitude-dependent rotation period of the Sun (averaging 28 days) is slower than a 24-day major solar flare period, with a constant Heliographic coordinate Active Longitude (in Heliographic Coordinates) we should see a drift of Earth-viewed longitudinal concentration of flares to other longitudes (in Stonyhurst Heliographic Coordinates) away from the limbs. References: Active Longitude (60% of flares are located within +/- 36° from the active longitude in Heliographic coordinates): https://ui.adsabs.harvard.edu/abs/2016ApJ...818..127G/abstract https://ssg.group.shef.ac.uk/progress/dissemination/ESWW2015_Gyenge_belgium_V3.key.pdf 24-day period between major flares: https://ui.adsabs.harvard.edu/abs/2004cosp...35.1395T/abstract