First, the government does not destroy any file completely. There will always be a computer record of the petition.Second, there are time limits for acting once a petition becomes current. One of the reasons is that one or more immigrant visas has been allocated to the petition. Given the lengthy waiting period for many family-based visa categories, it is reasonable to place a limit on how long one has to act once notified by NVC that a petition is ready for further processing.Unless there are extremely compelling circumstances that prevented one from timely acting on a notice from NVC, if the statutory period has passed, then a new petition is necessary. If the petition is in a preference category that is over subscribed, then a new priority date will be established, the priority date from the abandoned petition will not carry forward to the new petition.One should speak to an attorney to better understand their options.