P487IARU by the Aruba Amateur Radio Club. They will be active starting today until the end on the month. QSL information on QRZ.com
SK87WARD by the Föreningen Sveriges Sändareamatörer. They will be active on the HF bands (CW SSB and PSK31) from 00z to 24z only on April 18th. QSL via buro or SM6JSM; probably also LoTW.
This stations join other stations previously reported and some of them are on the air as you read this note:
6H6IARU, 3G87IARU, LZ1WARD, EL2RL, HB9WARD, HF87WARD, CR6IARU and KP4FD