Just looked in the warranty manual...
The factory warranty is 3 years / 36K miles, but there are a few things that are limited to less. One of those things is 'refrigerant'.
Here is the wording:
View attachment 8475
I would interpret this to mean that the A/C system is covered under the 3Y / 36K. If something fails and the repair entails replacing refrigerant then it is covered.
Of course, if a stone punctures the system that's not covered. The gray area is if your refrigerant leaks out slowly over time (your likely scenario), then they may balk. The reality is that this is supposed to be a sealed system, and a small leak could very likely be a defect in a component, or a manufacturing / assembly defect. To me, that should be covered within the 3Y / 36K. It probably depends on the nature of your service guy, and how you approach them.
There is always that fine line when you are just beyond the time / miles... A reasonable service manager should honor the 24K if you have 24.1K, but you better get in there pronto !
Anyone else have an opinion about this one?