That's a great reminder. Returns are due on the 15th day of the fifth month after the end of your fiscal year for PTOs and PTAs that are tax exempt under section 501c3 of the federal tax code. Stated more clearly, for most parent groups that's November 15th if the end of your fiscal year is June 30, and it's December 15th if your fiscal year ends July 31.
If you have a June 30 year end and you are a 501(c)(3) tax exempt organization, note that your 990EZ or postcard return is due on November 15! Check and make sure your Treasurer has filed your tax return.