Y UMI maxima

Affiliation
American Association of Variable Star Observers (AAVSO)
Sat, 02/06/2021 - 19:13

I have looked at the Y UMi light curve from the beginning of 2017 to date. The star has reached 5 maxima in this time span and it is currently reaching the 6th maximum. Looking at the light curve it seems to me that every other year the maximum appears to be substantially flat before the star fades. The effect can be seen in infrared.

Any idea about this behaviour?