وَهُوَ مِنَ الْجِنْسِ الَّذِي أَعْلَمْتُ أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَدْ صَلَّى الضُّحَى فِي غَيْرِ الْيَوْمِ الَّذِي كَانَ يَقْدَمُ فِيهِ مِنْ غَيْبَةٍ .
And this belongs to the same category which I have mentioned, that the Prophet Muhammad (peace be upon him) performed the Duha prayer on days other than the day of return from travel.