Have a look at this 800 days lightcurve of WY GEM:
http://www.aavso.org/lcg/plot?auid=000-BBK-812&starname=WY%20GEM&lastday... [1]
There seem to be two distinct "populations" of observations. Is there a misidentification, are two sets of comparison stars, ... ?
Links:
[1] http://www.aavso.org/lcg/plot?auid=000-BBK-812&starname=WY%20GEM&lastdays=800&start=&stop=2456334.2674562386&obscode=&obscode_symbol=2&obstotals=yes&calendar=calendar&forcetics=&grid=on&visual=on&pointsize=1&width=800&height=450&mag1=&mag2=&mean=&vmean=
[2] http://www.aavso.org/forums/variable-star-observing/visual-observing
