A two hours serie of CH Cyg (10 min. time resolution) with VHIRES MO spectrograph (R = 50 000 resolution) and Kepler 200 mm telescope (challenging small telescope observation - for the fun!). From 24.099 to 24.178 April, no chance, only a very small variation of Halpha line profile:
(here the two extreme date on the same graph and H2O telluric lines removed).
View of some part of CH Cyg spectrum (stack of 12 x 600 sec. exposures):