If you were granted Cancellation, then you will receive your green card. Depending on when you received the decision and your circumstances at the time, the judge may not have been able to grant your case. The visas for Cancellation are all gone for this year UNLESS you were in custody when you received the decision that your case was granted.
I am not sure why anyone would tell you that you have to wait a year but you should consult with an experienced immigration attorney to review your paperwork because it does not make sense that you would receive a grant of cancellation of removal based on a EOIR 42B right now.
This answer does not constitute legal advice, and should not be relied on as each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.
Once the immigration judge issued the decision granting cancellation of removal you in fact were granted adjustment of status. Before the decision becomes final, however, you have to wait 30 days from the date of the service of the decision. If the Government files an appeal then you will have to wait for the Board of Immigration Appeals to decide the appeal. If the 30 days elapse without an appeal been filed by ICE then the grant becomes final and you will be processed for a green card issuance. After the 30 days and if no appeal is filed by the government make an INFOPASS and go to the local USCIS office for post-final decision processing (digital picture etc.) for the production of the card.