I wouldnt read into it that much. If it was that predictable all of wall street would trade this thing down and any other stock that reports earnings on a Thursday.
Watch stocks that report earnings on Thursday between now and April 15th. If every single one of them reports bad earnings then sell your holdings. Otherwise get some sleep and worry about more significant things.
I find it more peculiar that they first said 3/29 release and then silence... then ok 4/15. The delay (or miss communication) is odd. Hope it's not a move to have more time to do damage control! ;-) Just saying.
I wouldn't over analyze the day of the week.
Am praying that they show a positive number for Q4 that allows for the FY to be positive numbers as well.