Idol Stars with the Shortest Training Time BTS Jimin - 6 Months. Lovelyz Yein - 4 Months. EXO Baekhyun - 4 Months. Super Junior Kyuhyun - 3 Months. A PINK Eunji - 2 Months. LOONA Olivia Hye - 1 Day. HA:TFELT (Wonder Girls Yeeun) - No Training Period. fromis_9 Gyuri - No Training Period. Jun 15, 2022