Yuji Nakamura (Kameyama, Mie, Japan) has reported the discovery of a possible nova, PNV J23244760+6111140, on March 18.4236. It is relatively bright at mag. 8 and may brighten more so worth a look. Here’s a finder chart prepared by Alan Pickup.
Nova Cas 2021 is at RA 23 24 47.73 Dec +61 11 14.8 (J2000.0)