What constitutes a geographically remote absence (Ghaibah Munqatti'ah) permitting a distant guardian to contract a marriage?

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A geographically remote absence is defined as a situation where correspondence (a letter) cannot reach the guardian, or if it reaches him, he does not reply. This condition is established because the affairs of the woman cannot be fully managed or consulted upon in such a distance, making it impossible for her to be married while waiting. Al-Qadi defined this distance as one where caravans do not travel back and forth more than once a year, as the suitable match should not be waited upon for more than a year, lest harm befall the woman by delaying her marriage. Abu Bakr held that the limit is what cannot be severed except with difficulty and hardship, referencing Imam Ahmad's statement that if no paternal relative is present, a letter is sent to them unless the absence is geographically remote (Ghaibah Munqatti'ah), which requires trouble to reach, in which case the ruler acts as the guardian. This view, that the standard rests on what is customarily considered an unsuitably long wait that causes harm and loss of potential suitors, is the nearest to correctness, as explicit textual demarcation is absent.