Antonyms for the phrase "as is the custom" include "unconventional," "abnormal," "unusual," "uncommon," or "unorthodox." These words refer to a deviation from established norms or traditions. Other antonyms could be "flexible," "adaptive," or "changing," signifying a willingness to evolve and adapt to new circumstances. People who reject established customs might describe themselves as "innovative," "nonconformist," or "pioneering." This type of thinking can lead to new discoveries or social change, but it can also cause tension or conflict with those who value tradition. Ultimately, the search for antonyms of "as is the custom" reflects the tension between the comfort of the familiar and the possibilities of the unknown.