"So early by now" is a phrase that denotes something happening sooner than expected or earlier than usual. There are several synonyms that can be used to replace this phrase, including "prematurely," "untimely," "premptorily," "precedent," and "prevenient." "Prematurely" refers to something happening before the planned time, while "untimely" suggests that something is happening at a time when it is not suitable. "Preemptorily" implies an action taken before others can act, and "precedent" suggests that something is happening before a similar event. "Prevenient" refers to something happening beforehand, paving the way for a later occurrence. These synonyms can add variation to one's language while maintaining the original meaning of the phrase.