So thanks to the heads-up from @Sabrinaklai, I've been tracking the flight prices on United and JetBlue for the last few weeks. It's been interesting, not leastwise because yesterday was the 90-day mark before my cruise, and today United's fares dropped like a rock to just barely more than the best price I'd seen when I'd started. Flight itinerary -- EWR to FLL on Wednesday, March 29; returning April 9 JetBlue "Blue Plus" fare selected for all price checks, since it includes one che