Re: NSV21190: eclipsing symbiotic star currently undergoing symbiotic nova outburst?
The object turned out to be an R CrB star.
https://www.aavso.org/vsx/index.php?view=detail.top&oid=59625 https://ui.adsabs.harvard.edu/abs/2020A%26A...635A..14T/abstract
Relatively periodic behavior in 2017-2020 would suggest the pulsation origin like DY Per stars.
vsnet-rcb@ooruri.kusastro.kyoto-u.ac.jp