Yes there are, in fact the "Ultime class" was not officially a class until recently, but just a "collectif"(group without formal status), it is now formally a class since Feb 15 or something called "Ultim 32/23" (max length, max width), and they have rules, but I could not find them online... (no web site for the class yet apparently)
Some rules can be revised every year, some every 4 years.
Regarding the foils, a key current rule is that they cannot automate the cant and rake (at least for the main foils), and this is a major point of contention with Gitana team, which I think has already done it, or wants to do it quickly, reason why Gitana Maxi 17 isn't part of the class currently.
And this rule is part of the ones that can be revised every four years, see for instance below :
But the collectif already had the rules, so I'm not sure when the "start date" is.
Also not sure what classification will be used for the route du Rhum.
Regarding the Gitana foils, I couldn't find any picture of the new ones (on the amas), I wonder whether they are very different or not from the previous ones which were quite different from the Banque pop ones for instance.