In your context, it sounds like you already know how the dairy you want to eat affects you. In that case, there's no reason for you to do a controlled reintroduction on that food group: you've already got the information you need. The idea behind reintroduction is to test for when you don't know how a food group impacts you physically/psychologically, and/or you want to know how eating that food will affect you.
Some folks separate out different types of dairy on different days. For example, they don't know how cow's milk impacts them vs. sheep's/goat's milk. Those people would do three different cow's milk products on one day, and then three different sheep's milk products on another day. Or a pasteurized dairy day vs. raw dairy day. Soft cheese day vs. hard cheese day.
It's your experiment of 1: test for what makes sense in the context of what you already know, don't yet know and/or want to discover.
Welcome all newcomers, welcome back vets, and for those of you who never left...welcome to this post.
I just wanted to pop in here and remind you all to take a deep breath before you dive into all the questions about what you can and can't have. The program guidelines are clear on what you can and can't have (grains, dairy, W30 muffins), but things get a little grey when people start talking about what you should and shouldn't have. Please don't over think think this. You don't have to address every food related issue you have, break every bad habit, and shun every food that gives you comfort to succeed with your Whole30. If you need to you can always extend or repeat the process, and things will get better each time you do. My advice to you is this:
Stick to the rules like they are your port in a storm (really, they will become that).
Take the Moderators responses seriously (we know what we're talking about).
Take community members suggestions as advice from those who came before, but keep in mind they are not the rules and not the Mods. Everyone here is well-meaning, and everyone here wants to see you succeed, but everyone here is at a different place in this journey.
And finally, take comfort in these words (from Melissa Hartwig, on another forum post):
Here's the thing (and this is an interesting discussion)... there are Whole30 "rules," which are strict, clearly outlined, and very well defined. No grains - and here are all the things we consider grains. No dairy - and here are all the dairy items excluded. No Paleo-fied food choices, and here's what those look like.
Then, there are Whole30 suggestions for success. They're not part of the official rules, but they're things that we've seen really help (or harm) people as they move through the program. Fruit smoothies for breakfast - not a good idea. Skipping breakfast - not a good idea. Eating every two hours, all day - not a good idea. These things won't necessarily affect your Whole30 results (although they might), but if we can give you additional suggestions that will make your transition and your program easier and more effective, we're going to give them to you.
Keep Calm and Whole30 On.