The announcement below was posted on the USCIS website. It relates to the delays in processing.

The EB-1 category grants an individual the “priority worker” status.  To qualify, the individual has to show that he or she is internationally renowned in a particular field, and that the individual will continue to work in that field upon arriving in the U.S.
 

1.  This bulletin summarizes the availability of immigrant numbers during December. Consular officers are required to report to the Department of State documentarily qualified applicants for numerically limited visas; the Bureau of Citizenship and Immigration Services in the Department of Homeland Security reports applicants for adjustment of status.

The H-3 classification (also known as the “trainee” visa) allows an individual to enter the United States to receive training in any field or endeavor so that the individual may pursue a career outside the United States.