Are S-parameters related to 180deg shifter for push-push microstrip oscillator?

I can't understand, S-parameters affect somehow 180deg phase line between active devices of push-push oscillator? There are few S parameters, wich of them must be taken into account, or maybe none of them?

In case of common resonator, if resonator itself is a 180 deg phase, i think lines from resonator to both oscillators can be any lenght, but certainly equal (for example, optimal length for basic oscillator, then just coupled to common resonator).