In cool temperate regions, there is one generation per year, with females active in the early summer and males and pre-diapausing females active in the late summer. Only mated females survive the winter. This is probably because unmated females cannot enter diapause.
In temperate climates, there is one breeding season per year, with females active during the early growing season and males and pre-winter females active during the late summer. Only mated females are able to withstand the winter, likely due to their reproductive status.