I did get a reply back from the elite@ email address - but in typical fashion, they cheerfully replied to half of my question - “you are welcome to bring an umbrella on any of our flights”… which was only half the question - the other half was “will it count towards my carry-on allowance?” But I’d already decided to shove it into one of my longer bags diagonally, and just juggled the clothing around it. Not ideal but easier than carrying 2 carry-ons + personal item (laptop bag) + umbrella and somehow also showing the team my boarding pass without dropping something and holding up the line!