SN3, I'm not disagreeing with you, and I believe you're absolutley correct when it comes to our regulations (I assume you need to conform to the FAA ones as well). I, and every operator and inspector I've ever met follows the first day to last day of a named month principle. I just don't want to make my statements definitive of every country in the world, where the words may have a different meaning (or things are lost in traslation).