Is it essential with regard to the Sunnah prayers that are done before the fard prayer that the time for that fard prayer should have begun?

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What do those who think that prayers in qiyaam al-layl should be offered two (rak‘ahs) by two say about the hadeeth of Mu‘aadh ibn Jabal (may Allah be pleased with him)?
Al Sunnan Al Rawatib (Sunnah Prayers associated with Fardh Prayers)

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What do those who think that prayers in qiyaam al-layl should be offered two (rak‘ahs) by two say about the hadeeth of Mu‘aadh ibn Jabal (may Allah be pleased with him)?
Al Sunnan Al Rawatib (Sunnah Prayers associated with Fardh Prayers)

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