When you want to express that something will continue to happen from a certain point onward, there are several synonyms you can use for the phrase "from that day/time/moment etc. forward." Some of the most common options include "since then," "henceforth," "hereafter," "from now on," and "from that point forward." Each of these phrases conveys the idea that a change has occurred, and that things will now proceed differently. Depending on the context and tone of the writing, one of these synonyms may be more appropriate than another. Consider which one best captures the mood and meaning you wish to convey.