Is it permissible to start more than one recitation (khatmah) of the Quran at the same time without finishing the first one, then complete them both together?

Reciting the Quran is among the best acts of worship. Whoever recites a single letter from it will receive a good deed, which will be multiplied tenfold. This reward is obtained by reading any Surah, whether it is part of an organized ختمة (complete recitation) or a casual reading.

It is better for a Muslim to continue their ختمة from the beginning of the Quran to its end, in the order of the Surahs, and not to start a new ختمة until they have finished the one they began. This was the practice of the Pious Predecessors (Salaf). One should not deviate from this except for an acceptable reason, such as having two different ختمات (e.g., one during prayer and one outside of it, or one for looking and one for memorization, or one for rapid recitation and one for contemplation). Otherwise, there is a fear that such an action might stem from haste and impatience.