XM78HT = AT 2021abog (UG) https://www.aavso.org/vsx/index.php?view=detail.top&oid=2225109
The current outburst began on 2021 October 15 according to ASAS-SN Sky Patrol (Shappee et al. 2014ApJ...788...48S and Kochanek et al. 2017PASP..129j4502K) data: https://asas-sn.osu.edu/sky-patrol/coordinate/45247e54-7a67-4e39-b69d-21913c... https://asas-sn.osu.edu/sky-patrol/coordinate/1520ddd9-d0f1-4592-9cf3-ac9619...
Time-resolved photometry is encouraged.
Clear skies, Patrick
vsnet-alert@ooruri.kusastro.kyoto-u.ac.jp