The phrase "when occasion permits" refers to a situation when something can be done, given the right circumstances. There are several synonyms that can be used in place of this phrase, including "as circumstances allow," "when feasible," "when possible," "if circumstances permit," and "when the opportunity arises." These phrases indicate that an action can be taken, but it is dependent on a specific set of circumstances. Other synonyms could include "when conditions are favorable," "when the time is right," or "when it is appropriate." All of these phrases convey a sense of readiness to act, but only when specific conditions are met.