The employer must withdraw the petition and the underlying LCA. Your petition is likely in the Public Access File which you should be able to review. Whether or not you're currently in status pursuant to a cap subject petition will determine if a new employer can file for you.
For CAP exception purposes, yes.
NYC EXPERIENCED IMMIGRATION ATTORNEYS www.myattorneyusa.com; email: firstname.lastname@example.org; Phone: (866) 456-8654; Fax: 212-964-0440; Cell: 212-202-0325. The information contained in this answer is provided for informational purposes only, and should not be construed as legal advice on any subject matter.
Your situation depends on issues not disclosed in your question and it also time sensitive. I suggest your new potential employer contact an experienced immigration attorney to determine whether he/she is qualified to employ you for an H visa.
Kyndra L Mulder, Esquire
4110 Southpoint Boulevard, Suite 101
Jacksonville, Florida 32216
(Across from the USCIS in Jacksonville)