have a read here regarding the I-864 rules:
http://www.visajourney.com/forums/index.ph...mp;#entry599625"What happens when the affidavit of support isn't examined for sufficiency until months or even years after it was submitted? The new rule clarifies that the adjudicating official must consider the sufficiency of the affidavit of support based on the income reported for the year the I-864 or I-864A was submitted, not on the sponsor's income on the date the application for adjustment of status or an immigrant visa is adjudicated. Similarly, adjudicators must use the federal poverty income guidelines in effect at the time the affidavit of support is submitted, not at the time it is considered for sufficiency. For that reason, all sponsors must submit Form I-864P, Poverty Guidelines, with the affidavit of support. In the event that more than one year has passed from the date of submission to the date of adjudication, USCIS or DOS officials may, in the exercise of discretion, request additional evidence, such as income tax returns for the most recent tax year. In those cases, it will be the sponsor's income and poverty income guidelines in effect for the year the adjustment or immigrant visa application is adjudicated that will control, not for the year the affidavit of support was originally submitted.
The INS stated in a 2000 policy memo that the affidavit of support must be legally sufficient at the time the adjustment of status application was approved, not at the time the affidavit was filed. That policy allowed adjustment applicants to submit an affidavit of support showing income below the required level, provided they supplemented it at the adjustment interview showing proof of sufficient income. USCIS has recently reversed its position on this issue and has now determined that the affidavit must be sufficient both at the time of filing and at the time the adjustment application is adjudicated. The NBC already has been following that procedure when it vets the affidavit of support as part of the process of preparing the adjustment application for adjudication. Beginning Nov. 23, 2005, all adjustment applications have to be filed centrally and must include the I-864."