Really the only deals for DCL is to either book on board, book when the dates are first released, or wait to see if they come out with the restricted GT rates a couple months before the cruise. They usually do that once the paid in full date has passed and if there are still rooms available. Or wait for any florida or military discounts (if you qualify for those).
Last minute *GT rates typically are offered after the paid in full date on those cruises that DCL deems as not selling well. It's a crap shoot as to what specific cruises those might be.
The only way to know what cruises have those discount rates are to just keep an eye on the cruises you're interested in. Once DCL decides to offer *GT rates (if they are going to) it will show up on the page where you select your category of room you want:
We have.... I thought it was pretty awesome too Last year we sailed on the Fantasy in January for $2900 for 2 A, 1 C (5). It was a VGT rate and we booked it about 70 days out. I just happened to be checking one day and these showed up. We haven't been able to get anything even close to it lately, not even IGT. I think Jan and Feb were a great time to get an IGT/OGT/VGT on the Fantasy PRIOR to Disney making these sailings Star Wars... There was an IGT for one of the Star Wars sailings I think late Feb/early March 2016 and the rate was $3700, so while not to bad $800 more than we paid the year before for a verandah.
I believe that if any of the GT rates will come out it will be for Sept and Dec on the Fantasy. They have some right now for July or August but prices still crazy as it's summer.
Even though it's nothing you can bank on, you have a chance for December. Start checking about 90 days out.
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