The spelling of the phrase "letted off time" can be confusing to some because it is not a common expression. The phonetic transcription of the word is /lɛtɪd ɒf taɪm/. It is derived from the verb "let off," which means to release or discharge something. Therefore, "letted off time" implies that someone has been released from work or another obligation early. The word "letted," while less commonly used, is the simple past tense of "let off."