Is it considered a violation of the Sunnah for someone to prolong the prostration (sujud) in the night prayer (qiyam al-layl) beyond the bowing (ruku') due to their need for supplication (du'a)?

The Sunnah indicates that prostration is a place where prayers are answered, and it is the closest a servant can be to his Lord. Prolonging prostration is better than prolonging other pillars except for standing. It is permissible to prolong prostration for supplication, provided one is not the Imam and it does not burden the congregants. As for the one praying alone, he may prolong it as much as he wishes, but without excess; because the principle in the actions of prayer—other than standing and sitting for Tashahhud—is moderation and near equality.