In computing any period of time prescribed or allowed by this chapter, by order of the executive director or board, or by any applicable statute, the period shall begin on the day after the act, event, or default in question, and it shall conclude on the last day of that designated period, unless the last day is a Saturday, Sunday, or legal holiday, in which event the period runs until the end of the next day that is not a Saturday, Sunday, or a legal holiday.