I thought this was funny as it came up on the same day as the white sneaker poll by Angie. (FWIW i wear white shoes all year round.)
DEAR MISS MANNERS: Is there still a certain time frame for when you can and cannot wear white? Also, do folks still wear slips under dresses?
GENTLE READER: Now! You can wear white now!
And don't waste another minute, because the time frame is Memorial Day to Labor Day, so you can only do so for two more weeks.
No, Miss Manners is not deluded enough to think that anyone waited for her permission on such a crucial manner. The truth is that she relishes seeing people work themselves into a froth over this. No rule of etiquette, no matter how strict, annoys people more than the one that reserves white shoes for the summer months.
Why it upsets them, she cannot imagine, considering how easily they all get away with ignoring it.
Still less is Miss Manners able to see, much less judge, whether folks are still wearing slips.