How is a determined term ('Ajal) interpreted when specified vaguely or related to calendar divisions?

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When a term is set to conclude at the beginning of a month (e.g., 'until the month of Muharram'), the term attaches to the first day of that month. Similarly, if the term is named after something that encompasses two entities, such as 'Jumada' or 'Rabi', the term attaches to the first of those two. If one states 'until three months,' the term concludes upon the completion of those three months, as the commencement is taken from the time of utterance. This is analogous to stating 'until one month,' where the end is determined upon its completion. These months are understood to be the lunar months, evidenced by the verse stating that the count of months according to God is twelve, four of which are sacred, indicating the lunar cycle (Quran 9:36). If the specified period begins mid-month, the remaining two months are completed based on the lunar cycle, and the final month is counted as thirty days. If the specification is phrased as 'in such and such a month' or 'on such and such a day,' it is valid and attached to the beginning of that period. This principle is established by analogy to divorce declarations, where stating 'you are divorced in such and such a month' takes effect from the start of that month.