This year is featuring several short-term special call signs as well as a permanent change in Spain. The South African Radio League is celebrating its 95th anniversary this year and the country's regulatory authority has authorized a special call of ZS95SARL to be used throughout 2020. SARL reports that different clubs will be activating the call at different times, based on a schedule that was still being finalized at press time.
Also in the Southern Hemisphere, the Cairns Amateur Radio Club in Australia is celebrating the semisesquicentennial (250th anniversary) of an historic trip by Captain James Cook up Australia's east coast from what is now Sydney to far northern Queensland, where Cairns is located. Southgate Amateur Radio News reports that the club has been authorized to us VI250COOK from May 1 through August 31. During this time, Cook's trip will be replicated by the Australian Maritime Museum's replica of his ship, the Endeavour. The call will also be used by clubs along the route as the ship makes its voyage. See the VI250COOK entry on qrz.com for more info.
Finally, Spain has authorized the issuance of permanent 2x1 call signs to qualifying amateurs. EA5BB, for example, is becoming EA5U. According to the ARRL Letter, the new short calls will be available to Spanish hams who have at least 15 years of "international amateur radio" experience and have never been sanctioned by the regulatory authorities.