This hadith has been narrated on the authority of Shu'ba with the same chain of transmitters but with this addition that he (the Holy Prophet) said:" Take advantage of the concession of Allah Who Wanted it to you." When he (one of the narrators) asked him (the other one, Yabya b. Abi Kathar) he did not retain it in his mind.
وَحَدَّثَنَاهُ أَحْمَدُ بْنُ عُثْمَانَ النَّوْفَلِيُّ، حَدَّثَنَا أَبُو دَاوُدَ، حَدَّثَنَا شُعْبَةُ، بِهَذَا الإِسْنَادِ . نَحْوَهُ وَزَادَ قَالَ شُعْبَةُ وَكَانَ يَبْلُغُنِي عَنْ يَحْيَى بْنِ أَبِي كَثِيرٍ أَنَّهُ كَانَ يَزِيدُ فِي هَذَا الْحَدِيثِ وَفِي هَذَا الإِسْنَادِ أَنَّهُ قَالَ " عَلَيْكُمْ بِرُخْصَةِ اللَّهِ الَّذِي رَخَّصَ لَكُمْ " . قَالَ فَلَمَّا سَأَلْتُهُ لَمْ يَحْفَظْهُ .
Muslim
The Book of Fasting • Hadith 120