April 17 – Antares-110 carrying PhoneSats v1a, v1b, v2a.
Dove-1 is also listed on this launch but it’s unclear if it’s using Amateur-Satellite Service frequencies.
April 19 – Soyuz-2-1a carrying OSSI-1, BEESAT 2/3 and SOMP
Dove-2 is also listed on this launch but it’s unclear if it’s using Amateur-Satellite Service frequencies.
April 20 – Vega carrying ESTCube-1 [Update now May 2]
April 26 – CZ-2D from the Jiuquan Space Center carrying the Mode J (145/435) linear transponder satellite TURKSAT-3USAT along with CubeBug-1 and NEE-01 Pegasus
https://amsat-uk.org/?p=14689 (NEE-01 has a downlink in the USA 902 MHz amateur band)
Note: planned launch dates can and do slip.