Cactus / theresai

The weather in this summer is unusal, repeated hot and cool.
I think this Mammillaria theresai f MZ364 has made a misjudgement of the season.
Mammillaria is in flower early spring normally but this one is in flower now.

I bought seeds and germinated in 2004. I grafted a young seedling.
Form MZ364 has different flower color from normal one.