Abd al-Rahman bin al-Aswad (may Allah have mercy on him) narrates from his father, from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him), concerning a man who was stung while he was in ihram for Umrah and was then prevented (from proceeding): Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said: "Send his sacrificial animal to Makkah, and fix a day between yourselves and him as a sign; when the sacrificial animal has been slaughtered in Makkah, he leaves ihram."
Abu Ubayd (may Allah have mercy on him) said: Al-Kisa'i said: Al-amar means "a sign" by which a thing is recognised; that is, fix a known day so that you do not differ.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10101