20 C.F.R. § 655.145
(b) Minor changes to the period of employment. The Application for Temporary Employment Certification may be amended to make minor changes in the total period of employment. Changes will not be effective until submitted in writing and approved by the CO. In considering whether to approve the request, the CO will review the reason(s) for the request, determine whether the reason(s) are on the whole justified, and take into account the effect any change(s) would have on the adequacy of the underlying test of the domestic labor market for the job opportunity. An employer must demonstrate that the change to the period of employment could not have been foreseen, and the crops or commodities will be in jeopardy prior to the expiration of an additional recruitment period. If the request is for a delay in the first date of need and is made after workers have departed for the employer's place of employment, the CO may only approve the change if the employer includes with the request a written assurance signed and dated by the employer that all workers who are already traveling to the place of employment will be provided housing and subsistence, without cost to the workers, until work commences. Upon acceptance of an amendment, the CO will submit to the SWA any necessary modification to the job order.
Post-Acceptance Requirements