Board Thread:Internal management/@comment-27138615-20170511172455/@comment-25029082-20170511173740

Kinda complicated, but you made it look like the Spongebob Wiki one, but better. Checks should be the following: or...
 * January 1
 * April 1
 * July 1
 * October 1
 * May 31
 * August 31
 * November 30
 * February 28/29