It is necessary to perform Qurbani at the time of Qurbani, therefore, if that much money or the same amount of goods to the value of an animal is given then the responsibility of Qurbani will not be fulfilled [Alamgiri etc.].
Qurbani can only be performed during the three days of Eid, namely the 10th, Ilth and 12th of Zulhijjah. It is only in these days that slaughtering of an animal is recognized as an act of worship. No Qurbani can be performed in any other days of the year. Although Qurbani is permissible on each of the three aforesaid days, yet it is preferable to perform it on the first day i.e. the 10th of Zulhijjah.
No Qurbani is allowed before the Eid prayer is over. However, in small villages where the Eid prayer is not to be performed, Qurbani can be offered’ any time after the break of dawn on the 10th of Zulhijjah.
Qurbani can also be performed in the two nights following the Eid day, but it is more advisable to perform it during daytime.
If the time of Qurbani has passed then a Qurbani can no longer be performed and if you had purchased an animal for Qurbani then give it as Sadqa or give the amount of money equivalent to the value of a goat as Sadqa [Durr-e-Mukhtar, Alamgiri, etc]