Class runoffs for Stock and Super Stock have been done on Thursday in the past.
Come to think, is Super Stock running at the Gators this year? The Gators is one of the events that drop one of the Sportsman classes on rotation. This is what NHRA calls their 'enhanced program'.
IIRC, last year was Stock, year before was SG. I'll be dissapointed if it is Super Stocks turn this year with all the new cars coming out.