USCIS has received a sufficient number of petitions to reach the congressionally mandated H-2B cap for the first half of Fiscal Year (FY) 2016. March 15, 2016 was the final receipt date for new H-2B worker petitions requesting an employment start date before April 1, 2016.
https://www.uscis.gov/news/alerts/uscis-reaches-h-2b-cap-first-half-fiscal-year-2016