Guth's position in this context would be that there was no change 'before' inflation meaning that time did not exist.

My understanding is that Guth accepts some kind of 'eternal inflation' hypothesis that inflation moves forward sometime after the planck time scale. He might, in that perspective, accept that there were events prior to inflation. The reason why I say so is I just read an article he wrote earlier in the year titled "Time Since the Beginning". Inflation had to come before baryogenesis, but he was reluctant to pick a time when inflation had to occur.