An extremely stuffy phrase used by business executives to close emails when they don't understand how to ask a real question. It basically means "Please use your imagination to figure out what the fuck I need to know to make a decision on this item without making me look like an idiot in front of all the people I CCed"
"Please Advise" is typically used in place of "Thanks" in formatting an email. It is very passive aggressive. Always assume that the user of the phrase "please advise" is a college graduate that follows the advice of his professors to a T... Even 15 years later..
I recently got a call from Alex in LA telling me that we're out of blinkity blank in California so the blippity blue isn't working. What-the-fuck what-the-fuck we're losing 15k a day what-the-fuck save me please.