HS Vir: possible superoutburst YYYYMMDD(UT) mag observer 20160402.485 158 (Rod Stubbings) 20160406.474 158 (Rod Stubbings) 20160408.462 160 (Rod Stubbings) 20160415.667 137 (Hiroyuki Maehara) 20160417.433 144 (Rod Stubbings)