Breeding season or not, I don't change too much in my calling techniques unless the coyotes seem to be resisting the calls. Sometimes, however, it DOES seem pretty apparent that the coyotes are more interested in "hooking up" than feeding, so I do try a few tricks from time to time when things seem a little slow:
Locator calls... I don't usually use locators, but they seem more effective during breeding season. It seems like males are more willing to investigate intruders during the breeding season.
Female scent or coyote scent... If fresh heat scent is available, it can be used to peak the interest of males, but last year I started using "Coyote in a stick" type scents. During the more "territorial" breeding season, coyotes will be more apt to investigate intruders than usual.
Just listen to the night... During hot breeding seasons, I'll drive around some of my favorite haunts and just listen. Coyotes "in love" are much less wary than normal, so sometimes you'll be able to hear either contesting pairs of males, locating younger coyotes, or mating pairs just by driving around and dropping the window. Once I hear something, I'll kind of assess what calls to put up, or if I can simply stalk to within range.