Per the NJ State Series pamphlet handed out to all riders at the start of the season:
Rain Dates for State Qualifiers or the Championship will be posted on the NJBMX Forum, NJBMX webpage on the NJBMX.org website, and Brokenspokes.net. The host track of the rained out race will also place an announcement regarding the new date on their answering machine as soon as a new date is set.
Hope this helps.