What ended up happening? What did you end up fasting?
Fasted the 24 hours with no problem, didn't even need water, though i thought i'd be able to fall asleep for the first 9 hours of SYD-LAX but I was unable to. Got hungry more out of boredom than anything else, though there were plenty of movies to choose from. Then again I'm the type who, at the end of YK, would be totally okay to fast another couple hours. Thank goodness it was winter in Australia though, would have been much harder if it were hotter. When the time came to break I asked the FA to heat up my dinner from earlier, ate my snack and water that had come an hour or two before break fast time, ate dinner, and ate breakfast when it came out a few hours later. Hydrated as much as possible.
My seatmates probably thought I was crazy, refusing meals and beverages for 9 hours and then stuffing myself.
All this with a 5-hour layover in SYD during which I took the train downtown, did Shacharit at the Great Synagogue, walked down to the Opera House to take a selfie and prove I was there, and returned to the airport to discover that DL doesn't allow its Gold/Plat/Diamond members on intl flights to use partner lounges, it's only for intl biz/first or club members.
Having fasted 24 hours, I then independently decided that I would continue to fast while on the ground in LAX and CVG but not in the air, since it is a public fast while on the ground but not in the air. This may have had something to do with being upgraded LAX-CVG. It's hard to refuse food and drinks when they're basically being force-fed to you.
Regarding the Lewis meals--good but not fantastic, certainly better than the Borenstein I got on the way to SYD. Fish as expected for dinner due to it being the ninth of the nine days. Kosher snack, btw, was an apple, a pear, and an orange, which were in fact delicious and the perfect things to break my fast on but it's kind of messy to eat an orange on a plane. The snack was not actually from Lewis.
Biggest downside of all this was missing a lot of free booze, including a great lounge (VA lounge in Perth).
Any other questions?